FORSCHUNGSGESELLSCHAFT
KRAFTFAHRWESEN mbH
AACHEN
ANGEWANDTE FORSCHUNG, ENTWICKLUNG UND CONSULT
Determination of Weight
Elasticity of Fuel Economy
for Conventional ICE
Vehicles, Hybrid Vehicles
and Fuel Cell Vehicles
Report 55510
Forschungsgesellschaft Kraftfahrwesen mbH Aachen
Body Department
Final report
Determination of Weight Elasticity of Fuel Economy for
Conventional ICE Vehicles, Hybrid Vehicles and Fuel Cell Vehicles
Project number
55510
Contractor:
International Iron and Steel Institute
WorldAutoSteel
Middletown, OHIO 45044-6211
USA
Project manager:
Project engineers:
Dipl.-Ing. Martin Johannaber
Dipl.-Ing. Markus Espig
Dipl.-Ing. Dipl.-Wirt. Ing. Roland Wohlecker
Group Leader Structural Analysis and Benchmarking
All rights reserved. No part of this publication may be reproduced and/or
published without the previous written consent of fka.  fka
Univ.-Prof. Dr.-Ing. Henning Wallentowitz
Dr.-Ing. Jörg Leyers
Head of ika
Managing Director fka
Aachen, June 2007
Managing Director: Dr.-Ing. Jörg Leyers, Chairman of the Advisory Board: Univ.-Prof. Dr.-Ing. Henning Wallentowitz
Registered in Aachen HRB 2435, Dt. Bank, Bank code 390 700 20, Account no. 201 339 900
IBAN: DE 31 3907 0020 0201 339 900, SWIFT-Code (BIC): DEUTDEDK 390
Steinbachstraße 7, D-52074 Aachen Phone: +49 / (0)241 / 88 61-0 Fax: +49 / (0)241 / 88 61-110
27777 Franklin Road, Suite 300, USA-Southfield MI 48034 Phone: +1 / 248 / 213-02 53 Fax: +1 / 248 / 213-02 99
Contents
3
Contents
1
Executive Summary .........................................................................................................5
2
Introduction.......................................................................................................................8
3
Literature Research..........................................................................................................9
3.1
Internal Combustion Engine Vehicles ........................................................................9
3.2
Hybrid and Fuel Cell Vehicles ..................................................................................11
4
Fundamentals.................................................................................................................12
4.1
Hybrid Vehicles ........................................................................................................12
4.1.1
Serial Hybrid Drivetrain.........................................................................................13
4.1.2
Parallel Hybrid Drivetrain ......................................................................................14
4.1.3
Combined and Power Split Hybrid Drive ..............................................................15
4.2
5
Fuel Cell Vehicles.....................................................................................................17
Simulation.......................................................................................................................20
5.1
Vehicle Analysis .......................................................................................................20
5.2
Simulation Approach ................................................................................................21
5.3
Simulation Results....................................................................................................22
5.3.1
Influence of Powertrain Re-Sizing ........................................................................24
5.3.2
Influence of the Vehicle Class ..............................................................................25
5.3.3
Influence of the Powertrain Technology ...............................................................26
5.3.4
Influence of the Driving Cycle ...............................................................................26
5.3.5
Conclusions ..........................................................................................................26
6
Summary ........................................................................................................................28
7
Literature ........................................................................................................................29
Contents
8
4
Appendix ........................................................................................................................33
1
Executive Summary
1
Executive Summary
5
A comprehensive simulation study in order to investigate the relationship between mass
reduction and fuel consumption was conducted. This study was executed by Forschungsgesellschaft Kraftfahrwesen mbH Aachen (fka) on behalf of the International Iron and Steel
Institute Automotive Committee (IISI-AutoCo).
Content of Study
In this study the influence of a weight reduction on the fuel consumption was analysed by
simulation. In doing so three different vehicle types (compact, mid-size, SUV), five different
propulsion systems (gasoline engine, diesel engine, gasoline hybrid, diesel hybrid, fuel cell)
and two different driving cycles (NEDC, HYZEM) were considered. The study also contains a
literature survey which analyses the current perceptions about mass sensitivity of internal
combustion engine vehicles, hybrid vehicles und fuel cell vehicles. Besides the analysis of
the vehicles with its base weight and a reduced weight, vehicles with a reduced weight and
an powertrain re-sizing were examined as well in simulation. All simulation results were
compared and assessed. In addition the fundamentals of the alternative propulsion systems
were explained.
Overview of Results
In the literature survey the most suitable results are found for ICE vehicles. The result values
are in a range of 4.5 % to 6 % fuel consumption reduction per 10 % weight saving and
0.15 l/100 km to 0.7 l/100 km fuel consumption reduction per 100 kg weight saving
respectively. These results include papers of the automobile, steel and aluminium industry.
Unfortunately at most of the literature sources the boundary conditions of measurements or
statements are not always clearly defined. One very valuable source was found in [WAL00].
In the simulation approach the vehicle weight reduction was determined considering primary
and secondary weight saving effects. The simulations were conducted for vehicles with the
base weight, for vehicles with the reduced weight and for vehicles with reduces weight and
re-sized powertrain. All simulations are done for three vehicles classes, five propulsion
systems and two driving cycles. As a software the widely spread tool Matlab/Simulink® was
used. The simulation results are displayed in Fig. 1-1 and Fig. 1-2.
1
6
Executive Summary
Compact Class
Mid-Size Class
SUV
-1.9
-2.6
-2.4
-2.7
-2.6
-3.1
-3.5
-2.9
-3.6
-3.9
-4.5
-4.9 -4.9
-5.3
-4.9
-5.7
-5.8
-6.0 -5.9
-6.3
-6.8
-7.0
-7.1
-8.2
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
Fig. 1-1:
-7.9
-7.4
-7.7
-4.7
-5.1
-7.1
in [%]
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain
Influence of 10 % weight reduction on fuel consumption in NEDC cycle
Compact Class
-3.1
-3.4
-3.2
Mid-Size Class
-3.0
-3.4
SUV
-3.0
-3.2 -3.4
-3.2 -3.4 -3.3
-3.8
-4.2
-4.9 -4.8-4.9
-5.0
-5.1
-5.4
-5.5 -5.5
-5.9
-6.8
-5.5
-5.7 -5.6
-4.6
-4.6
-5.2
-6.6
in [%]
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
Fig. 1-2:
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain
Influence of 10 % weight reduction on fuel consumption in HYZEM cycle
1
Executive Summary
7
It was found that at a 10 % mass reduction without powertrain re-sizing saves fuel between
1.9 % and 3.2 % in conventional vehicles with gasoline engine and between 2.6 % and 3.4 %
with Diesel engine when considering both driving cycles. When considering the powertrain
re-sizing at ICE vehicles this effect has a bigger influence than the mass reduction itself,
especially in the NEDC cycle. Further on the effect of powertrain re-sizing (in combination
with mass reduction) has less effect in hybrid powertrains due to the reduced impact of idling
losses and avoidance of low efficiency operating points. It was established that the ICE
vehicles are more mass sensitive than hybrids and FC vehicles when considering powertrain
re-sizing, but less mass sensitive without considering powertrain re-sizing. But all in all it is
important that, when talking about weight sensitivity the used boundary conditions have to be
strongly considered, because the results are influenced by many parameters.
2
Introduction
2
Introduction
8
In the scope of the important discussion about the raising CO2 emissions a simulation study
was conducted to analyse the relationship between mass reduction and fuel consumption.
The study is commissioned by International Iron and Steel Institute Automotive Committee
(AutoCo) to receive exact information about the influence of mass reduction to the amount of
fuel consumption. Within this project three different vehicle types with three different
propulsion systems will be examined when also considering two driving cycles. All the
simulated results will be compared with collected literature information.
In order to get an overview about the current perception of the weight elasticity a literature
study will be carried out. In this literature study the relationship of mass reduction and fuel
consumption in internal combustion engine vehicles, hybrid vehicles and fuel cell vehicles in
combination with the related boundary conditions will be analysed. All information will be
compared and documented in tables.
The basis for the simulation itself is built by an analysis of three vehicle types. The generic
mass of compact class, mid-size class and sport utility vehicles and their body structures will
be determined. The fuel consumption of these generic vehicles will be established, as well as
the fuel consumption for these vehicles with reduced mass. In addition the influence of a resizing of the powertrains will be considered. The simulation work will also be done for the
propulsion systems hybrid and fuel cell.
The simulation will be done with the software Matlab/Simulink®, a tool widely used for
dynamic system simulations and control development at all OEMs and mayor suppliers. The
simulation is executed using the driving cycles NEDC and HYZEM. The results of all
simulations will be analysed and compared, based on that conclusions will be drawn. The
results will be filed in tables and illustrated with charts. For every main issue of this study one
chapter is prepared. All results are summarised in the corresponding appendices.
The main issues of the simulation study are:
•
Literature research (chapter 3)
•
Fundamentals (chapter 4)
•
Simulation (chapter 5)
3
Literature Research
3
Literature Research
9
A literature research is conducted especially in order to find current values of weight elasticity. The weight elasticity value expresses the ratio of the percentage of fuel consumption
reduction and the percentage of mass reduction (see appendix 3-1). In addition to that further
information about the relationship of mass reduction and fuel consumption is gathered. The
aim was to find values of internal combustion engine vehicles, hybrid vehicles and fuel cell
vehicles. The literature survey is done in the most important automotive engineering magazines, SAE-papers, papers from technical congresses etc. It has to be considered that the
amount of literature with regard to the weight elasticity of fuel consumption published for
hybrid vehicles and especially for fuel cell vehicles is much smaller than for vehicles with
conventional drive-trains.
3.1
Internal Combustion Engine Vehicles
The most promising results are found for internal combustion engine vehicles. Several
results deliver values of fuel consumption reduction when reducing the vehicle weight for
10 %. In further literature sources the fuel consumption reduction in the unit “litre per 100 km”
is mentioned when a vehicle weight reduction of 100 kg is considered. Further information is
shown in appendix 3-2. The important results are listed in Fig. 3-1.
Weight Saving
Fuel Consumption Reduction
Source 1 [SCH04]
10 %
4.7 %
Source 2 [THO99]
10 %
4.5 %
Source 3 [RUC99]
10 %
6%
Source 4 [DAS00]
10 %
5%
Source 5 [FRE02]
100 kg
0.4 l/100 km
Source 6 [SCH96]
100 kg
0.5 l/100 km
Source 7 [PIE92]
100 kg
0.6 l/100 km
Source 8 [FUR01]
100 kg
~ 0.35 l/100 km
Source 9 [SPR92]
100 kg
~ 0.65 l/100 km
Source 10 [RAU99]
100 kg
~ 0.6 l/100 km
Source 11 [GEB00]
100 kg
0.5 l/100 km
Source 12 [STO96]
100 kg
0.15 l/100 km
Source 13 [AUE01]
100 kg
~ 0.35 l/100 km
Source 14 [RID98]
100 kg
up to 0.6 l/100 km
Source 15 [BAU98]
100 kg
~ 0.65 l/100 km
Fig. 3-1:
Important literature results for internal combustion engine vehicles
3
Literature Research
10
The sources of the literature research are mainly independent institutes, organisations, OEM
and supplier, but also sources of the steel and aluminium industry. In many cases the
relationship between weight reduction and fuel consumption is mentioned in only one
sentence in the articles. In the most cases the boundary conditions of the measurements and
the statements and the consideration of secondary weight saving effects are not always
clearly defined. Furthermore it is significant that the result values are spread in relatively wide
range.
Very good information is provided by the literature source [WAL00]. This report describes the
examination of eleven different gasoline and diesel powered vehicles of different vehicle
classes on a dynamic roller test bench. In these tests ten different driving cycles are
considered. The measurements are done with the basic vehicle weight and for comparison
with 100 kg weight reduction. In every case the fuel consumption is determined. No
secondary weight saving effects are considered. All results are in a range of 0.02 to
0.47 l/100km. When analysing only the NEDC driving cycle the average result value of all
analysed vehicles is 0.18 l/100km. That means a weight reduction of 100 kg leads to a fuel
consumption reduction of 0.18 l/100km. When calculating the corresponding averaged
weight elasticity value of all analysed vehicles only for the NEDC driving cycle the result is
0.36. Further analysis values are shown in the corresponding appendix 3-7.
Further information about the relationship of mass reduction and fuel consumption is given in
source [RID98]. Lynne Ridge describes the results of a EUCAR survey. The result values are
based on technical simulations and empirical data. In this study the fuel reduction of gasoline
and diesel powered vehicles in litre per 100 km is determined when reducing the vehicle
weight for 100 kg.
Fig. 3-2:
Results of fuel consumption reduction in [l/100km x 100kg] [RID98]
The analysis is done without and with gear ratio change. Based on the result values a WEV
of 0.38 is calculated. Unfortunately the way of calculation is not mentioned. Despite of this
result of 0.38 a WEV of 0.6 for automotive LCA studies is recommended. The source
[SCH04] uses the information of [RID98] for a life cycle assessment in a case study. Further
information about [RID98] is shown in the corresponding appendix 3-11.
3
3.2
Literature Research
11
Hybrid and Fuel Cell Vehicles
For the literature research on HV all available search engines were used but the paper
dealing specific with mass impact in hybrid vehicles are very rare. Several dozen of papers
dealing with the fuel economy of hybrid vehicles were read without finding valuable
information on mass impact.
The most important source of information concerning HEV is the SAE paper 2004-01-0572
from An/Santini with the title “Mass Impact on Fuel Economics of Conventional vs. Hybrid
Electric Vehicles” [AN04]. Therein the correlation between fuel economics and vehicle mass
for production HEV with different levels of hybridisation is presented (see appendix 3-14) and
it is examined how this relationship evolves from CV to HEV. According to this paper there
are two important impacts of shifting from conventional to hybrid vehicles in terms of the
mass vs. fuel economy relationship. With little or no change in mass there are significant
improvements in fuel economy possible. But, once a switch to hybrid powertrains has been
made, the effectiveness of mass reduction in improving fuel economy will be diminished
relative to conventional vehicles.
4
Fundamentals
4
Fundamentals
12
In order to provide some background to the technology of hybrid and fuel cell vehicles, a
basic introduction to hybrid and fuel cell powertrain technology is given.
4.1
Hybrid Vehicles
By definition, a hybrid drive system consists of two different drive systems, i.e. at least of two
energy converters and two energy storages. This definition shows in principle, that the term
“hybrid drive” covers a multiplicity of possible variants. The different essential structures of
the combination of combustion engine, e-machine, gas turbine, battery and planetary
transmission for the serial, the parallel and the combined/power-split hybrid drive are
represented in Fig. 4-1.
serial
hybrid drive
V
V
GT
E
E
E
B
E
B
...
B
EE
EE
V
V
B
E
parallel
hybrid drive
V
...
B
E
EE
combined/
power split
hybrid drive
V
E
PL
E
E
E
B
B
B
PL
E
E
...
B
battery
Fig. 4-1:
V
V
E
electric machine
engine / generator
V
combustion
engine
Basic structures of hybrid vehicles
GT
gas turbine
PL
planetary
transmission
4
13
Fundamentals
Beside the fundamental hybrid structures, hybrid drives can be differentiated additionally by
installed electrical power and stored electrical energy (see Fig. 4-2).
rate of drive train system [%]
Parallel hybrids of small installed power and electrical energy storage are also designated as
starter-generator hybrid. If the electrical power is a little higher dimensioned, it is called
power assist hybrid or, related to the energy content of the electrical energy storage, low
storage hybrid.
combustion engine + generator
fuel cell
electrical
storage
electric motor
electric motor
combustion engine
conv.
combust. drive
parallel hybrid
power split hybrid
power assist hybrid
low storage hybrid
integr. starter/generator
Fig. 4-2:
electrical
storage
pure e-drive
(battery)
serial hybrid
combined hybrid
range extender
pure e-drive
(fuel cell)
electr. IVT
low storage hybrid
Classification in installed power and storage capacity
The serial hybrid with a large battery and a small auxiliary power unit (APU) is called a range
extender. If the energy content of the battery is limited small, which results in a small
emission-free range, the hybrid is called a low storage hybrid. If there is not any storage
integrated in the electrical intermediate circuit, the drive system works with an electrical IVT
(infinite variable transmission). In the broader sense, a fuel cell vehicle with additional
electrical energy storage is also a serial hybrid vehicle. Hybrid drives, whose electrical
energy storage cannot be charged from electric energy net, are called self-supporting
hybrids.
4.1.1
Serial Hybrid Drivetrain
Characteristic of serial hybrid drives is the "series connection" of the energy converter
without mechanical coupling of the combustion engine to the drive wheels (see Fig. 4-3).
Here, the combustion engine drives a generator, which supplies the electrical drives as well
as a storage arranged in the electrical intermediate circuit (usually a battery) with energy.
There are variants with a drive engine and a differential as well as concepts with two drive
engines per axle, which do not require the differential, up to wheel hub drive motors.
14
transmission
electric motor
alternator
IC engine
Fundamentals
fuel tank
4
battery
Fig. 4-3:
Serial hybrid drive
4.1.2
Parallel Hybrid Drivetrain
In the parallel hybrid drive systems (Fig. 4-4), combustion engine and electric motor are
mechanically coupled to the drive wheels. Beside the two drive units (engine/motor) and two
storages, a parallel concept contains one or several transmissions, clutches, or freewheeling
clutches. The two propulsion systems can be used individually and at the same time for the
propulsion of the vehicle. Due to the power addition they can be laid out relatively small.
Usually the electric drive type is designed for city traffic (limited, emission-free driving
operation), while the combustion engine provides higher performances for overland traffic
and motorways. The produced electrical and combustion engine energy can be overlaid mechanically by means of speed-addition (with a planetary transmission), torque-addition (with
gearbox with spur-cut gear or chain), or traction power addition (electric motor and
combustion engine affect different drive axles). For torque-addition, the relation between the
torques of two energy converters can be varied freely, while the speed relation is fixed. A decoupling of the two drive systems can be realized by a freewheeling clutch or the clutch.
fuel tank
IC engine
transmission
battery
Fig. 4-4:
Parallel hybrid drive
electric motor
4
15
Fundamentals
For the addition of speeds, the powers of the energy converters are added by a planetary
transmission, whereby the torque relation is fixed and the speed of the drive systems can be
selected independently. In the physical sense, a hybrid with traction power addition is
likewise a torque addition concept, in which the two energy converters affect different axles
of the vehicle (e.g. the electric drive influences the front axle, the combustion engine is
coupled on the rear axle).
A further possibility for the distinction of parallel hybrids occurs due to an arrangement of the
energy converters. If both drive systems (electric motor and combustion engine) are coupled
directly to the input shaft of the transmission, it is called a single-shaft hybrid. A two-shaft
hybrid consists of an electric motor and a combustion engine arranged on different
transmission shafts (transmission in or output shaft).
4.1.3
Combined and Power Split Hybrid Drive
electric motor
alternator
IC engine
fuel tank
A combination of parallel and serial structures is the so-called combined or power split hybrid
[ESS98]. With combined hybrids (Fig. 4-5), it is possible to transfer the power of the combustion engine directly to the wheels by closing the clutch, which is an improvement of the
overall efficiency in certain operating conditions (e.g. the high power demand of motorway
driving). At the same time both electric machines can deliver their power additionally, like a
parallel hybrid and briefly increase the maximum power. The higher expenditure faces the
improved efficiency by the clutch and the more complex operating strategy. Furthermore, the
arrangement of combustion engine and generator cannot be designed freely any longer, as a
direct mechanical coupling to the drivetrain must take place.
battery
Fig. 4-5:
Combined hybrid drive
Power split hybrid drives represent a further, however, very complex possibility of hybrid
drives. With these structures a part of the power of the combustion engine is transferred
directly mechanically to the drive wheels; the remaining power is transferred e.g. by a
planetary transmission and two electric motors to the drive wheels. Generally a battery is
used for energy storage. With this arrangement of the electric motors, the system works as a
4
16
Fundamentals
Fig. 4-6:
electric motor
planetary gear
alternator
IC engine
fuel tank
continuous variable transmission, so that an additional transmission is not necessary for the
combustion engine. In principle, the combustion engine can be operated speed and powerindependently of the other powertrain components. The efficiency level is higher than with
serial structures due to the partial direct mechanical power transfer.
battery
Power split hybrid drive
The Toyota Hybrid System II (THS II) is such a power split parallel hybrid drive consisting of
a 1.5 l, 4-cylinder, 57 kW Otto engine that works according to the Atkinson/Miller process and
a 50 kW permanent magnet electric motor. These components together with a generator are
connected by a planetary transmission, which facilitates a power split. Here, the combustion
engine is connected with the bar, a generator with the sun wheel. The electric motor is
coupled with the ring gear on the one hand and directly supplied by a chain drive with the
system on the other hand (Fig. 4-7). The planetary gear splits the power of the combustion
engine between the wheels and the generator in dependence on the vehicle operating
condition.
Fig. 4-7:
Power split hybrid with planetary gear
4
17
Fundamentals
This facilitates to operate the combustion engine on a mostly consumption-favourable range.
By using the planetary transmission and the generator, the system works similar to an
electronically regulated CVT and does not need a clutch. The generator speed regulates the
speed control of the planetary gear and thus, the combustion engine (Fig. 4-8). The
generator supplies its energy either directly to the electric motor or stores it into a battery.
generator
rotational speed
increase
of
generator
power
combustion engine
rotational speed
increase
of engine
power
sun gear
Fig. 4-8:
electric-motor
rotational speed
acceleration
bridge
internal gear
Speed dependency in Kutzbach plan
The concept represents a self-supporting vehicle, i.e. a charge of the batteries by the electric
energy network is not intended since the operating strategy possibly keeps the battery in a
certain charging status. In principle, the hybrid drive in the Toyota Prius has only one
operating mode, which regulates the drive engines automatically. A purely electrical
operation is only possible at low speeds.
4.2
Fuel Cell Vehicles
A fuel cell vehicle is propelled by an electric motor, which is powered by the fuel cell stack.
Hydrogen or hydrogen-rich gas and air are converted into electricity and heat in the fuel cell
stack. The heat which is released during the process has to be cooled off. Fuel gas and air
streams have to be pressurized and humidified. In direct hydrogen fuel cell vehicles, the
hydrogen is stored in high pressure tanks, cryogenic tanks, or metal hydride storage
containers. Indirect methanol or other indirect hydrocarbon fuel cell vehicles carry a fuel
reformer to produce a hydrogen-rich synthesis gas from a liquid fuel. The complexity of the
process makes detailed models for the prediction of vehicle characteristics necessary.
The fuel cell system comprises the fuel cell stack, the air and fuel conditioning, and the water
and thermal management. Output of the fuel cell system is electricity, which is supplied to the
electrical motor or to the energy storage.
4
Fundamentals
18
In the fuel cells itself hydrogen and oxygen are combined to water. Hydrogen molecules are
split into protons and electrons at the fuel cell anode. A proton exchange membrane
conducts the protons to the cathode, while the electrons induce an electrical current which
can be used as a power source. Electrons, protons, and oxygen molecules are combined at
the fuel cell cathode in the presence of a platinum catalyst. The electrical current is
proportional to the amount of hydrogen molecules converted. Ideally, the difference in the
electro-chemical potential between anode and cathode dictates the voltage. This open-circuit
voltage is reduced when a current between the two electrodes flows. With increasing current
these losses increase. They can be attached to different mechanisms:
-
Anode overpotential losses: reaction losses due to oxidation of hydrogen at the
anode catalyst
-
Cathode overpotential losses: reaction losses due to the reduction of oxygen at the
cathode catalyst
-
Gaseous diffusion losses in the anode and cathode backing layer
-
Ionic resistance to the proton conduction in the membrane
-
Electronic resistance of the catalyst, backing layer, and bipolar plates
-
Water management in the membrane
-
Pressure drops in the anode and cathode channel and the effect on the partial
pressure of hydrogen and oxygen, respectively, at the catalyst layers
-
Anode air bleed to mitigate effect of CO poisoning
A decrease of cell efficiency can be observed when the partial pressures of hydrogen or
oxygen are lowered. Insufficient membrane humidification also decreases the cell efficiency.
Unconverted hydrogen in the anode exhaust stream can only be recycled to the anode feed
in direct hydrogen fuel cell systems. In indirect fuel cell systems the hydrogen concentration
in the original reformate stream is too low, further dilution with the depleted anode exhaust
would have an additional negative impact on the cell efficiency. Hydrogen remaining in the
anode exhaust can instead be burnt in a burner. A major power sink in pressurized fuel cell
system is the air compressor. The air supplied to the cathode is in some systems
compressed to 2 to 3 atmospheres (absolute). Sometimes, part of the compression energy is
recovered in an expander that is placed in the cathode exhaust stream. In load-following
vehicles the air compressor has to be responsive to changes in the power demand to supply
the necessary amount of oxygen to the fuel cell. The control of the air compressor has to
keep the performance close to the most efficient operating point.
Compressors usually have a minimum amount of air that has to be turned over and cannot
be switched off completely. This minimum power is decisive for the energy consumption of
the vehicle at low power demands.
4
Fundamentals
19
Although average efficiencies of fuel cell stacks are higher than those of internal combustion
engines (ICE), the cooling system is more challenging. In ICE vehicles a large part of the
heat is released in the hot exhaust gas, only about half of the heat (roughly 30 % of the
energy contained in the fuel) has to be removed by cooling fluids and dissipated by the
radiator. Maximal cooling fluid temperatures for ICE can be around 120 °C. The heat
generated by the fuel cell stack (about 60 % of the fuel energy) is released at a lower
temperature (80 °C) and has to be cooled off by a radiator primarily. Only a small fraction of
the heat is carried out of the system via the exhaust stream. A larger amount of excess heat
at a lower temperature necessitates a bigger radiator surface. Another challenge to the water
and thermal management (WTM) is the need for humidification of the proton exchange
membrane. Its conductivity is related to the saturation with water. Humidification of the
membrane is obtained by saturating the fuel gas and supplied air. Drying up of the
membrane leads to losses and can eventually burn out the cell. The necessary water can be
taken from the cathode exhaust stream but has to be condensed, causing again higher
radiator surface. Too much humidification of the input streams, on the other hand, can lead
to flooding of the cell. The term ”flooding” describes the effect of blocking of diffusion paths in
the gas diffusion backing layer and of reaction sites on the catalyst on the cathode side by
liquid water.
In most fuel cell vehicle designs a common power bus distributes the energy supplied by the
fuel cell stack to the motor, the fuel cell stack accessories, and some of the auxiliary systems
like heating and air conditioning. In hybrid fuel cell vehicles the system also contains an
energy storage device, which is charged in times of lower power demand from the motor,
and discharged when the power demand of the motor is high. The operation strategies for
the energy storage can be complex. Unlike in electric vehicles, the design of the battery is
not optimised towards high energy capacities to guarantee the range requirement of the
vehicle. Instead important criteria are high maximum current, high power, and short response
times.
The efficiency of the electric motor, defined as the ratio of power at the motor shaft to
electrical power at the motor terminals, depends on the motor speed and the torque at the
motor shaft. While the available motor torque is limited by a maximum torque value at low
motor speeds, the maximum torque at higher motor speeds is dictated by the total motor
power. Since the maximum current that the motor can handle is limited, the available motor
power at higher motor speeds decreases with lower system voltage, which is the voltage that
the fuel cell stack and the battery can provide [HAU00b]. Fuel cell stack voltage and battery
voltage decrease at high power outputs. This is one of the complex interrelationships
between the components in the fuel cell vehicle that makes also the modelling a challenging
task.
5
Simulation
5
Simulation
5.1
20
Vehicle Analysis
In order to achieve a realistic vehicle weight reduction the body-in-white is analysed for a
potential weight reduction and the possible influences on the complete vehicle weight. It is
assumed that the body-in-white weight can be reduced by using an optimised design, more
high strength steels or further lightweight materials. This data is necessary as an input for the
simulation process.
In this study three different vehicle types are analysed. Therefore the vehicle weight and the
body-in-white weight for typical vehicles of these vehicle classes are determined (see
appendix 5-1). Based on this data generic values are generated. The generic vehicle
characteristics are shown in Fig. 5-1.
Class
Compact
Mid-size
SUV
Fig. 5-1:
Engine
Capacity
Power
Mass
Example
4 Cylinder
1600 cm3
85 kW
1260 kg
Ford Focus
6 Cylinder
3
181 kW
1640 kg
Mercedes E-Class
3
235 kW
2195 kg
BMW X5
8 Cylinder
3000 cm
4500 cm
Determination of generic vehicles
Based on the determined generic body-in-white weight the primary weight saving is
calculated. The assumption is made, that it is possible to reduce the body-in-white weight for
about 20 to 40 %. Therefore these both limits are considered for the further weight
calculations (Fig. 5-2). The weight values of both paths are used in the simulations.
Class
Vehicle
mass
Body structure
mass
Primary
weight saving
Compact
1260 kg
360 kg
72/144 kg
22/43 kg
1166/1073 kg
Mid-size
1640 kg
400 kg
80/160 kg
24/48 kg
1536/1432 kg
SUV
2195 kg
540 kg
108/216 kg
32/65 kg
2055/1914 kg
Fig. 5-2:
Secondary
Reduced
weight saving vehicle mass
Weight values of generic vehicles (at 20 and 40 % primary weight saving)
The secondary weight saving is assumed to be 30 % of the primary weight saving. This
weight reduction step considers weight reduction in further vehicle components due to the
less body-in-white weight (see appendix 5-6). The reduction of the secondary weight saving
is estimated based on to a suitable method from ThyssenKrupp Steel used in the NSB® study
(see appendix 5-7). This secondary weight saving value is calculated for both paths of the
calculation (for 20 and 40 % primary weight saving). In addition to that a separate simulation
is done for both paths with considering the powertrain re-sizing. In doing so the powertrain is
5
21
Simulation
adapted to the lower weight in order to achieve the same acceleration as the basis vehicle.
This method is described in chapter 5.2.
5.2
Simulation Approach
For the calculation of the fuel consumptions of the contemplated vehicle classes and
powertrain configurations the simulation tool Matlab/Simulink® is used. This tool is used for
dynamic system simulation and control development by all OEMs and major suppliers in the
automotive industry (see appendix 5-12). The required characteristic values and maps of all
vehicle components are stored in Matlab in the form of vectors and matrices. Simulink
provides the modelling of the physical dependencies in a graphical user interface which is
shown in appendix 5-21. The single components, e.g. combustion engine, electric motor,
transmission and clutch, are available in special libraries at fka and can be connected in a
modular architecture to build up different powertrain configurations. Matlab/Simulink® permits
the investigation of the time dependent system behaviour so that e.g. shifting and clutch
operations can be displayed (see appendix 5-19).
The following vehicle simulations are executed in the driving cycles NEDC and HYZEM. The
NEDC, shown in appendix 5-17, is the standard synthetic cycle for consumption measurement in Europe. The HYZEM is a common cycle used to represent the real world traffic
which means a more dynamical course of velocity containing higher acceleration and deceleration values (see appendix 5-18).
Anode
conventional
vehicle
Fig. 5-3:
parallelhybrid
fuel cell
vehicle
Overview of the powertrain configuration used in the simulation
5
Simulation
22
In the course of the simulative investigation three different powertrain technologies are
analysed in three different vehicle segments. An overview of the powertrain architectures is
depicted in Fig. 5-3. The basis vehicles (ICEV) are equipped with an internal combustion
engine and a manual transmission (see appendix 5-26). The hybrid vehicles (HV) contain a
parallel arrangement with a clutch between the combustion engine and the electric motor and
another clutch between the electric motor and the transmission (see appendix 5-29). This
arrangement in conjunction with a traction battery offers the possibility of pure electric
propulsion as well as electric boost power and recuperation of braking energy. In the change
from conventional ICEV to a hybrid vehicle the size and power of the internal combustion
engines keeps unchanged. This adds some extra weight to the vehicle because of the hybrid
components, but at the same time power from the electric motor is added, so that the
acceleration performances of the hybrid vehicle is actually better than the one of the internal
combustion engine.
The fuel cell vehicles (FCV) are equipped with a fixed gear ratio and a battery (see
appendix 5-32) which enables the recuperation of braking energy as well as the phlegmatic
operation of the fuel cell. The fuel cell powertrain in the vehicles is sized to provide the same
acceleration performances as the ICEV have. It is assumed that the weight of the powertrain
is a little bit more than that of a conventional one. Current fuel cell powertrains implemented
in prototype vehicles weigh a lot more than ICEV powertrains, but the aims for the power
density of fuel cell powertrains of all major developers are to reach a power density close to
that of an ICE powertrain. For the simulations performed, the same weight as for the hybrid
vehicles is assumed. The considered vehicle segments contain the compact class, the
middle class and SUV.
For the analysis of the influence of weight reduction in conjunction with powertrain re-sizing,
vehicle models with same performances are compared. Therefore the 0 to 100 kph
acceleration values of the basis vehicle (ICEV, HV, FCV) are calculated in the first step. After
that the vehicle weight is reduced by the defined primary and secondary weight saving. In the
next step the powertrain is scaled down so that the acceleration values of the lightweight
vehicle and the basis vehicle correspond (see appendix 5-20). In the simulation of the
lightweight hybrid vehicle the combustion engine and the electric motor are scaled down by
the same factor. For the fuel cell vehicle the electric traction motor and with it the fuel cell
system are scaled down.
5.3
Simulation Results
For an analysis of the weight influence on the fuel consumption several comparisons are
required. In the first step the influence of a simple weight reduction on the fuel consumption
is compared to the effect of weight reduction in conjunction with powertrain re-sizing.
Additionally the effects of weight reduction on the fuel consumption are compared for three
considered vehicle segments and for five considered powertrain set-ups. Besides the
influence of different load profiles is analysed by using a standard driving cycle (NEDC) and
5
23
Simulation
a more dynamic driving cycle (HYZEM). An overview of the simulation results is shown in
Fig. 5-4 and Fig. 5-5.
Compact Class
Mid-Size Class
SUV
-1.9
-2.6
-2.4
-2.7
-2.6
-3.1
-3.5
-2.9
-3.6
-3.9
-4.5
-4.9 -4.9
-5.3
-4.9
-5.7
-5.8
-6.0 -5.9
-6.3
-6.8
-7.0
-7.1
-8.2
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
Fig. 5-4:
-7.9
-7.4
-7.7
-4.7
-5.1
-7.1
in [%]
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain
Influence of 10 % weight reduction on fuel consumption in NEDC
Compact Class
-3.1
-3.4
-3.2
Mid-Size Class
-3.0
-3.4
SUV
-3.0
-3.2 -3.4
-3.2 -3.4 -3.3
-3.8
-4.2
-4.9 -4.8-4.9
-5.0
-5.1
-5.4
-5.5 -5.5
-5.9
-6.8
-5.5
-5.7 -5.6
-4.6
-4.6
-5.2
-6.6
in [%]
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
Fig. 5-5:
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain
Influence of 10 % weight reduction on fuel consumption in HYZEM
5
24
Simulation
5.3.1
Influence of Powertrain Re-Sizing
The results of the simulations in appendix 5-43 show that for conventional cars with gasoline
engine (ICEV-G) the influence of powertrain re-sizing on the consumption reduction in the
HYZEM driving cycle is about as important as the weight reduction. In the NEDC the fuel
benefit by powertrain re-sizing is more than twice as big as the weight influence because of
the low load profile in this cycle (see appendix 5-42). In conventional cars with Diesel engine
(ICE-D) the powertrain re-sizing is slightly less effective due to the higher part load efficiency
which results from the lack of throttling losses.
For the hybrid vehicles (HV-G and HV-D) the effect of powertrain re-sizing is much smaller.
This is due to the avoidance of lower part load operating points of the combustion engine by
means of pure electric propulsion and regenerative load. In contrast the influence of a simple
weight reduction to the absolute consumption reduction compared to ICEV is ambivalent
(see appendix 5-46 – 5-49). On the one hand the HV generally offers a higher tank to wheel
efficiency. That means that in the HV less fuel is necessary to provide a fixed amount of
energy for propulsion. As a result the corresponding reductions of driving energy for the
ICEV and the HV caused by the weight savings lead to less absolute consumption reduction
in the HV. On the other hand the efficiency of the ICEV becomes worth by lowering the load
level at same engine speed whereas the HV efficiency remains relatively constant due to an
consumption-optimised adaptation of the engine operating points to the lower load profile or
rather an extension of pure electric propulsion.
For the fuel cell powertrain the powertrain re-sizing can even have a negative impact on the
fuel savings. But the tendency changes with the vehicle categories and the driving cycle. The
reason for this is that contrary to an ICE powertrain the efficiency of the fuel cell powertrain
reaches a maximum at loads of 15 to 30 %, while the efficiency decreases at very low loads
and at high loads. The differences between the characteristics are depicted in Fig. 5-6.
η
50%
Combustion
Fuel
cell
Urban
Fig. 5-6:
engine
Suburban
Highway
Comparison of the efficiencies of ICE and fuel cell powertrains at different loads
5
Simulation
25
The characteristics of fuel cell powertrains lead to the changing tendency of the fuel
consumption reduction when re-sizing the powertrain system. In some cases a bigger system
(base powertrain) leads to a lower fuel consumption, because with constant power demands
of the driving cycle, the percentage load on the system decreases if the system maximum
power is increased.
In the NEDC the middle-sized car and the SUV show a higher fuel consumption with the
bigger system. Here the higher losses and therefore low efficiency at very low loads of the
bigger fuel cell systems are determining and can not be compensated by the better
efficiencies at higher loads, because the power demand of the NEDC cycle is very low. Only
the compact class vehicle benefits of the bigger system and has a lower fuel consumption
with the bigger system. The reason for the different tendency of the compact class vehicle is
the lower power to weight ratio, which was sized according to the acceleration demands for
this class, which is lower than for a middle-sized car or a SUV. The fuel savings of the
compact class vehicle with reduced weight are a little bit lower with the bigger system (base
engine) than with the re-sized system in the NEDC, where the power demand in not very
high.
In driving cycles with very high power requirements, bigger fuel cell systems have an
advantage, since the efficiency of a fuel cell system is lower at high power outputs than at
middle and low power outputs. Thus in the HYZEM cycle there is almost no difference
between the two fuel cell systems for the middle-sized car and the SUV, since even after the
re-sizing the systems are still very powerful. But in the compact class a difference between
the two powertrain sizes can clearly be seen. The compact class vehicles consumes more
fuel with the smaller (re-sized powertrain) fuel cell system. The re-sized powertrain is
operated at its maximum power output many times during the driving cycle, where the
efficiency drops down a lot, thus the consumption increases and the fuel consumption
reduction with 10 % of weight reduction is lower (see Fig. 5-5).
5.3.2
Influence of the Vehicle Class
The dependency of the absolute consumption reduction on the different vehicle segments,
compact class, middle class and SUV, is mainly influenced by the different characteristic
weights and motorisations (see appendix 5-27). As expected, the highest absolute
consumption improvement is achieved in the heaviest vehicle segment, with the most
powerful engine, the SUV. In contrast the lowest reduction is reached in the smallest
considered vehicle segment, the compact class (see appendix 5-42/43). An exception for the
HV-G is the relation between the consumption reduction of the middle class and the SUV in
the NEDC. Contrary to expectations the consumption improvement is lower for the SUV (see
appendix 5-46). This can be due to the non-linear system behaviour of the hybrid powertrain,
which results from the changeover between pure electric propulsion, pure combustion-engine
powered driving, parallel driving mode etc. In this particular case the adaptation of the energy
management of the hybrid SUV is not fitted as well to the NEDC as the energy management
of the middle class. In contrast the consumption reduction of the hybrid SUV in the HYZEM
5
Simulation
26
driving cycle is evidently higher than in the other segments, as expected (see appendix 5-47).
5.3.3
Influence of the Powertrain Technology
The influence of advanced powertrains on the consumption improvement by weight reduction
is analysed in a comparison of two conventional powertrain set-up with a gasoline or a Diesel
engine (ICEV-G and ICEV-D), two parallel dual clutch hybrid system with an electric motor
between the engine and the transmission, one with gasoline engine (HV-G) and one with
Diesel engine (HV-D) and a fuel cell vehicle (FCV) with an additional battery. The results of
the simulation study show that the absolute consumption improvement by weight saving
including powertrain re-sizing becomes smaller in the contemplated advanced powertrain
set-ups, HV and FCV. The smallest reduction is achieved with the FCV, whereas the highest
fuel savings appear in the ICEV in particular in the ICEV-G due to the strong influence of
powertrain re-sizing (see appendix 5-53/54). Regarding the percentage changes of the fuel
consumption in appendix 5-34/36, the differences between the different powertrain
technologies are much smaller as a result of the inherent base consumptions which are very
low for the FCV and relative high for the ICEV.
5.3.4
Influence of the Driving Cycle
The influence of different load profiles on the fuel consumption improvement by weight
saving is analysed by means of the standard driving cycle NEDC and the more dynamic
driving cycle HYZEM. The absolute consumption reduction by weight reduction including
powertrain re-sizing is smaller in the HYZEM due to the higher engine base efficiency which
is a result of the higher load profile in this cycle. Besides the difference between the ICEV
and the HV in the total fuel consumption is much less in the HYZEM than in the NEDC. This
is due to the high power requirement which means that the engine also runs in the range of
low specific fuel consumption in the ICEV whereas the advantage for the HV by a
consumption-optimised choice of the engine operating range becomes less important and
the additional weight compared to the ICEV is disadvantageous. The effect of powertrain resizing is also much less in the HYZEM as a result of the extensive avoidance of lower part
load operating due to the high power requirement. In contrast the vehicle weight is more
important for the fuel consumption in the HYZEM (see appendix 5-35/37). This is a result of
the more dynamic run of the cycle which means that the mass dependent acceleration
resistance takes a bigger share of the total resistance.
5.3.5
Conclusions
The results of the simulation study have shown that for conventional powertrains the effect of
powertrain re-sizing has a bigger influence on the consumption reduction than the mass
reduction itself, especially in the NEDC. The absolute consumption improvement by weight
5
Simulation
27
saving including powertrain re-sizing becomes smaller in the contemplated advanced
powertrain set-ups, HV and FCV.
Furthermore the WEV have been calculated by means of the simulation results (see appendix 5-59). In general the WEV with powertrain re-sizing in the NEDC are higher than in the
HYZEM cycle. This is due to the bigger share of part load operating points in the NEDC
which can be reduced effectively by powertrain re-sizing. With the change from conventional
to alternative powertrains, the WEV with powertrain re-sizing decrease. This is due to the
smaller impact of the mass in alternative powertrains which means much less absolute
consumption reduction for HV and FCV at same weight reduction. Without powertrain resizing the WEV in HV are bigger than in ICEV which is not due to a higher absolute
consumption reduction, but to a lower base consumption and the higher absolute weight of
the HV. In general the significance of the WEV alone is not sufficient for an assessment of
the mass impact in different powertrain technologies. For this purpose the absolute consumptions at different masses are important.
6
Summary
6
Summary
28
For the investigation of the relationship between mass reduction and fuel consumption a
simulation study was conducted. In a first step the perception of the public was established
by surveying published literature. The determination of the weight reduction was done by
calculating the primary weight saving at the body-in-white and the secondary weight savings
at further vehicle components. In addition an powertrain re-sizing due to the lower vehicle
weight was performed. In the simulation step the three different vehicle types compact class
vehicle, mid-size class vehicle and sport utility vehicle were analysed. All of them were
combined with the five different propulsion systems gasoline engine, Diesel engine, gasoline
hybrid system, Diesel hybrid system and fuel cell system. The simulations were done with
considering two common driving cycles, the New European Driving Cycle (NEDC) and the
HYZEM cycle.
The literature survey delivers some suitable results for internal combustion engine vehicles
(ICEV). The result values are in a range of 4.5 % to 6 % fuel consumption reduction per 10 %
weight saving and 0.15 l/100 km to 0.7 l/100 km fuel consumption reduction per 100 kg
weight saving respectively. These results include papers of the automobile, steel and
aluminium industry. Unfortunately at most of the literature sources the boundary conditions of
measurements or statements are not always clearly defined. One very valuable source was
found in [WAL00]. Concerning hybrid and fuel cell vehicles very less results were found.
For the vehicle weight reduction primary and secondary weight saving effects were
considered. The simulations were conducted for vehicles with the base weight, for vehicles
with the reduced weight and for vehicles with reduces weight and re-sized powertrain. All
simulations are done for three vehicles classes, five propulsion systems and two driving
cycles. As a software the widely spread tool Matlab/Simulink® was used.
All results were compared and conclusions were drawn. It was found that at a 10 % mass
reduction without powertrain re-sizing saves fuel between 1.9 % and 3.2 % in conventional
vehicles with gasoline engine and between 2.6 % and 3.4 % with Diesel engine when
considering both driving cycles. When considering the powertrain re-sizing at ICE vehicles
this effect has a bigger influence than the mass reduction itself, especially in the NEDC
cycle. Furthermore the powertrain re-sizing (in combination with mass reduction) has less
effect in hybrid powertrains due to the reduced impact of idling losses and avoidance of low
efficiency operating points. It was established that the ICE vehicles are more mass sensitive
than hybrids and FC vehicles when considering powertrain re-sizing, but less mass sensitive
without considering powertrain re-sizing. But all in all it is important that, when talking about
weight sensitivity the used boundary conditions have to be strongly considered, because the
results are influenced by many parameters.
7
Literature
7
Literature
[AN01a]
AN, F.; VYAS, A.; ANDERSON, J.
Evaluating Commercial and Prototype HEVs
SAE paper 2001-01-0951
[AN01b]
AN, F.; DECICCO, J.; ROSS, M.
Assessing the Fuel Economy Potential of Light duty Vehicles
SAE paper 2001-01-2482
[AN03]
AN, F.; SANTINI, D. J.
Assessing Tank-to-Wheel Efficiencies of advanced Technology vehicles
SAE paper 2003-01-0412
[AN04]
AN, F.; SANTINI, D. J.
Mass Impacts on Fuel Economies of Conventional vs. Hybrid Electric Vehicles
SAE paper 2004-01-0572
[AUE01]
N.N.
Keine Monokultur
Automobil-Entwicklung, 2001
[BAU98]
BAUER, D.; KREBS, R.
Vor- und Nachteile von Aluminium als Karosseriewerkstoff
Metall, 52. Jahrgang, 1998
[DAS00]
DAS, S.
The Life-Cycle Impacts of Aluminium Body-in-White Automotive Material
JOM, 2000
[DAS03]
DAS, S.
Lightweight Opportunities for Fuel Cell Vehicles
SAE paper 2005-01-2007
[DIC99]
DICK, M.
Der 3-Liter Lupo - Technologien für den minimalen Verbrauch
VDI-Berichte 1505, 1999
[ENG99]
ENGELHART, D.
Die Entwicklung des Audi A2, ein neues Fahrzeugkonzept in der
Kompaktwagenklasse
VDI-Berichte 1505, 1999
[FEN01]
FENG, A., DECICCO, J.
Assessing the Fuel Economy Potential of Light-Duty Vehicles
SAE 2001-01-2482, 2001
29
7
Literature
30
[FRE02]
FREITAG, H.
A-Klasse und Polo setzen auf Leichtbau
Aluminium Kurier News (J), 2002
[FUR01]
FURRER, P.
Aluminium Karosseriebleche (ISBN 3-478-93250-5)
Aluminium Karosseriebleche, 2001
[GEB00]
GEBHARD, P.; WILK, T.; KOLL, S.
Gesamtfahrzeugparameter und die Auswirkungen auf Fahrleistung und
Verbrauch
Sonderausgabe ATZ/MTZ Audi A2, 2000
[GMC01]
N.N.
Well-to-Wheel Energy Use and Greenhouse Gas Emission of Advanced Fuel /
Vehicle Systems
General Motors Corp. e.a.
Internet: http://www.transportation.anl.gov/pdfs/TA/163.pdf, 2001
[GRA00]
GRAHAM, R. e.a.
Comparing the Benefits and Impacts of Hybrid Electric Vehicle Options
Internet: http://www.epri.com/attachments/286056_1000349.pdf, 2000
[HEL04]
HELLMANN, K. H.; HEAVENRICH, R. M.
Light-Duty Automotive Technology and Fuel Economy Trends: 1975 Through
2004
Internet: http://www.epa.gov/otaq/cert/mpg/fetrends/420s04002.pdf, 2004
[HER04]
HERMANCE, D.
New Efficiency Baseline 2004 Toyota Prius
Internet:
http://www.epri.com/event_attachments/2093_(05)HermanceNewEfficiency.pdf,
2004
[PIE92]
PIECH, F.
3 Liter /100 Km im Jahr 2000?
ATZ 94, 1992
[RAU99]
RAU, G.; e.a.
Aluminium- und Eisengußwerkstoffe im Vergleich
DVM-Tag, 1999
[RID98]
RIDGE, L.
EUCAR - Automotive LCA Guidelines - Phase 2
SAE paper 982185, 1998
7
Literature
[RUC99]
RUCKSTUHL, B.
Kostengünstiger Leichtbau
VDI Berichte 1505, 1999
[SAE01a] N.N.
Fuel Cell Technology for Vehicles
SAE PT-84, Hardback with a collection of 30 SAE papers, 2001
[SAE01b] N.N.
Fuel Cells and Alternative Fuels/ Energy Systems
SAE SP-1635, Hardback with a collection of 14 SAE papers, 2001
[SAE01c] N.N.
Fuel Cell Power for Transportation 2001
SAE SP-1589, Hardback with a collection of 16 SAE papers, 2001
[SAE02]
N.N.
Fuel Cell Power for Transportation 2002
SAE SP-1691, Hardback with a collection of 18 SAE papers, 2002
[SAE03a] N.N.
Fuel Cells: Technology, Alternative Fuels, and Fuel Processing
SAE SP-1790, Hardback with a collection of 7 SAE papers, 2003
[SAE03b] N.N.
Fuel Cell Power for Transportation 2003
SAE SP-1741, Hardback with a collection of 31 SAE papers, 2003
[SCH96]
SCHÄPER, S.; LEITERMANN, W.
Ganzheitliche Betrachtungen im Automobilbau
VDI Berichte 1307, 1996
[SCH04]
SCHMIDT, W.-P.; e.a.
Life Cycle Assessment of Lightweight and End-of-Life Scenarios for Generic
Compact Class Passenger Vehicles
LCA Case Studies 9, 2004
[SOV03]
SOVRAN, G., TROY, M.
A Contribution to Understanding Automotive Fuel Economy and Its Limits
SAE 2003-01-2070, 2003
[SPR92]
SPRINGE, G.
Durchbruch der Aluminium-Anwendung beim Bau von Automobil-Karosserien
Blech Rohre Profile 39, 1992
31
7
Literature
32
[STO96]
STOCKMAR, J.
Leichtbau - Eine besondere Herausforderung für die Großserie
VDI-Berichte Reihe 12 Nr. 267, 1996
[THO99]
THORWALD, E.
Und es bewegt sich doch
Bild der Wissenschaft, 1999
[VOL03]
VOLKHAUSEN, W.
Methodische Beschreibung und Bewertung der umweltgerechten Gestaltung von
Stahlwerkstoffen und Stahlerzeugnissen
Dissertation, 2003
[WAL00]
WALLENTOWITZ, H.; e. a.
Untersuchungen des Zusammenhangs zwischen Pkw-Gewicht und
Kraftstoffverbrauch – Messungen an 11 Fahrzeugen auf dem dynamischen
Rollenprüfstand
Research Report P374 of Studiengesellschaft Stahlanwendung e.V., Düsseldorf,
2000
[WEI00]
WEISS, M. A.; HEYWOOD, J. B.; DRAKE, E. M.; Schafer, A.; AuYeung, F. F.
On the Road in 2020
A life-cycle analysis of new automobile technologies
Energy Laboratory Report # MIT EL 00-003, 2000
8
Appendix
8
Appendix
33
Appendix
Content
Chapter 3: Literature Research
Chapter 4: Fundamentals
Chapter 5: Simulation
Appendix for
Chapter 3:
Literature Research
App. 3-1
Chapter 3: Literature Research
Weight Elasticity Value (WEV)
Necessary input data:
Curb weight (e.g. 1500 kg)
Fuel consumption (e.g. 10.4 l / 100km)
Mass reduction (e.g. 100 kg = 6.7 %)
Fuel consumption reduction (e.g. 0.3 l / 100 km = 2.9 %)
fuel cons. reduction [%] =
mass reduction [%] =
WEV =
abs. fuel cons. reduction [l]
fuel consumption [l]
abs. mass reduction [kg]
curb weight [kg]
fuel cons. reduction [%]
mass reduction [%]
=
e.g. WEV =
=
0.3 l
10.4 l
100 kg
1500 kg
2.9 %
6.7 %
= 2.9 %
= 6.7 %
= 0.43

App. 3-2
Chapter 3: Literature Research
Available Data for ICEV (1)
Curb
Weight
[kg]1
Fuel
Consumption
Weight
Savings
(absolute) / kg
Reduction of
Fuel Consumption
(absolute) / litre
Wallentowitz, H.;
e.a.
Untersuchungen d. Zusammenhangs zw. Pkw-Gewicht
u. Kraftstoffverbrauch (2000)
X*
X*
100
X*
X*
X*
Volkhausen, W.
Methodische Beschreibung
und Bewertung der
umweltgerechten Gestaltung
von Stahlwerkstoffen und
Stahlerzeugnissen (2003)
X*
X*
100
X*
X*
X*
Life Cycle Assessment of
Lightweight and End-of-Life
Scenarios for Generic
Compact Class Passenger
Vehicles (2004)
1000
8.1 l/100km
100
10 %
0.38
4.7 % **
Schmidt, W.P.;
e.a.
“EUCAR-Source”
Freitag, H.
A-Klasse und Polo setzen auf
Leichtbau (2002)
-
-
100
-
0.4
-
Schäper, S.
Ganzheitliche Betrachtung im
Automobilbau (1996)
-
-
100
-
0.5
-
1)
weight of the complete vehicle including filled tank (90%) and 75 kg for driver and baggage
* manifold data
** calculated value

App. 3-3
Chapter 3: Literature Research
Available Data for ICEV (2)
Curb
Weight1
Fuel
Consumption
Weight
Savings
(absolute) / kg
Reduction of
Fuel Consumption
(absolute) / litre
Piech, F.
3 Liter / 100km im Jahr 2000?
(1992)
chart
chart
100
chart
0.6
chart
Stockmar, J.
Leichtbau - Eine besondere
Herausforderung für die
Großserie (1996)
chart
chart
100
chart
0.15 / 0.4 ***
chart
---
Keine Monokultur (2001)
-
-
100
-
0.3 - 0.4
-
Bauer, D.
Vor- und Nachteile von
Aluminium als
Karosseriewerkstoff (1998)
-
-
100
-
0.6 - 0.7
-
Rau, G.
Aluminium- und Eisenwerkstoffe im Vergleich (1999)
-
-
100
-
0.5 - 0.7
-
Thorwald, E.
Und es bewegt sich doch
(1999)
-
-
-
10 %
-
4.5 %
Ruckstuhl, B.
Kostengünstiger Leichtbau im
System Konstruktion,
Werkstoff und
Fertigungstechnik (1999)
-
-
-
10 %
-
6%
1)
weight of the complete vehicle including filled tank (90%) and 75 kg for driver and baggage
*** wo/w secondary weightsavings

App. 3-4
Chapter 3: Literature Research
Available Data for ICEV (3)
Curb
Weight1
Fuel
Consumption
Gebhard, P.
Gesamtfahrzeugparameter
und die Auswirkungen auf
Fahrleistung und Verbrauch
-
-
100
-
0.5
-
Springe, G.
Durchbruch der AluminiumAnwendung beim Bau von
Automobil-Karosserien (2000)
-
-
100
-
0.6 - 0.7
-
Furrer, P.
Aluminium Karosseriebleche
(2001)
-
-
100
-
0.3 - 0.4
-
Ridge, L.
EUCAR – Automotive LCA
Guidelines – Phase 2 (1998)
-
-
100
-
0.02 - 0.60
-
Das, S.
The Life-Cycle Impacts of
Aluminium Body-in-White
Automotive Material (2000)
-
-
-
10 %
-
5%
1)
Weight
Savings
(absolute) / kg
Reduction of
Fuel Consumption
(absolute) / litre
weight of the complete vehicle including filled tank (90%) and 75 kg for driver and baggage

App. 3-5
Chapter 3: Literature Research
Available Data for ICEV (4)
Possible ways of fuel consumption reduction
Dick, M.
Der 3-Liter Lupo Technologien für den
minimalen Verbrauch (1999)
Automobil
Entwicklung
Ein Kilogramm kostet einen
Euro (2002)
Possible use of different materials for lightweight construction
purposes; costs of weight reduction process (Opel)
Engelhart, D.
Die Entwicklung des Audi A2,
ein neues Fahrzeugkonzept in
der Kompaktwagenklasse
(1999)
Development of fuel consumption
Hellmann, K. H.
Light-Duty Automotive
Technology and Fuel Economy
Trends: 1975 Through 2004
(2004)
Fuel consumption of light trucks (up to 8000 lbs.)
Feng, A.
Assessing the Fuel Economy
Potential of Light-Duty
Vehicles (2001)
Simulation of advantages through advanced engine and
transmission, lightweight materials, integrated starter-generator, and
hybrid drive for five car classes
Sovran, G.
A Contribution to
Understanding Automotive
Fuel Economy and Its Limits
(2003)
Basic physics of automotive fuel consumption for conventional and
unconventional powertrains
Sources contains no suitable values for purposes of this project

App. 3-6
Chapter 3: Literature Research
Available Data for ICEV (5)
Life cycle analysis with series vehicles of Volkswagen; no
relationship between weight reduction and fuel consumption
reduction mentioned
Schweimer, G.;
e.a.
Life Cycle Inventory for the
Golf A4 (2000)
Louis, S.
Life Cycle Assessment and Design-Experience from Volvo Car Corporation; SAE 980473 *
---
Life Cycle Analysis – Data and Methodologies Phase 2; EUCAR Final Report *
Kaniut, C.
Life Cycle Assessment of a Complete Car – The Mercedes-Benz Approach; SAE Paper 971166 *
LeBorgne, R.
Life Cycle Analysis: a European Automotive Experience *
Kapus, P.; e.a.
Intelligent Simplification – Ways Towards Improved Fuel Economy *
Magee, C. L.
The Role of Weight Reducing Materials in Automotive Fuel Savings; SAE Paper 820147 *
Gutherie, A. L.
Fairmont/Zephyr – Engineered for Lightweight and Improved Fuel Economy *
* not considered for purposes of this project, because no more new results expected; partly old documents

App. 3-7
Chapter 3: Literature Research
Detailed Results for ICEV (selected)
Source [WAL00]: H. Wallentowitz; e.a.
“Untersuchungen des Zusammenhangs zwischen Pkw-Gewicht und
Kraftstoffverbrauch – Messungen an 11 Fahrzeugen auf dem dynamischen
Rollenprüfstand”, Research Report P374 of Studiengesellschaft
Stahlanwendung e.V., 2000
Examination of 11 different vehicles (gasoline- and dieselpowered) on a dynamic roller testbench
Consideration of 10 different driving cycles
Weight reduction of 100 kg without secondary effects
Determination of reduction in fuel consumption
Results:
Reduction in fuel consumption of 0.02 to 0.47 l/100km (all driving cycles)
Reduction in fuel consumption 0.10 to 0.28 l/100km (only NEDC cycle)

App. 3-8
Chapter 3: Literature Research
Detailed Results for ICEV (selected)
Source [WAL00]: H. Wallentowitz; e.a. - Range of possible fuel savings for 11 vehicles (NEDC only)
0.70
Reduction Fuel Consumption [l/100km]
NEDC cycle
WEV
0.60
0.50
0.40
0.36
0.30
0.20
0.18
0.10
ni
c
tip
tr
o
74
0i
W
52
8i
M
2.
8
8
iA
ud
M
W
TD
B
B
A
M
er
c
ed
es
E2
90
E2
30
er
ce
de
s
M
ec
tr
a
1.
6
on
d
O
pe
lV
Fo
rd
M
G
ol
VW
16
V
eo
I
fT
D
C
L
VW
G
ol
f
1.
6
G
R
ot
20
5
Pe
ug
e
Pe
ug
e
ot
10
6
XR
D
0.00

App. 3-9
Aachen City
Aachen Highw.
Highway
FTP 75
NEDC
Euromix
const. 120
const. 90
ECE
Source [WAL00]: H. Wallentowitz; e.a.
Highw+slope
Chapter 3: Literature Research
Detailed Results for ICEV (selected)
Reduction of consumption [l/100km ]
0.00
-0.05
-0.10
-0.15
-0.20
-0.25
-0.30
Average Upper Class
Average Middle Class
Average Compact Class
Average All Classes
-0.35

App. 3-10
Chapter 3: Literature Research
Detailed Results for ICEV (selected)
Source [WAL00]: H. Wallentowitz; e.a.
ECE
const. 90
const. 120
NEDC
FTP 75
Highw+slope
Highway
Aachen Highw.
Aachen City
average all cycles
0.60
Weight elasticity value [-]
0.50
0.40
0.30
0.20
0.10
0.00
Average Upper Class
Average Middle Class
Average Compact Class

App. 3-11
Chapter 3: Literature Research
Detailed Results for ICEV (selected)
Source [RID98]: L. Ridge
“EUCAR – Automotive LCA Guidelines – Phase 2”; SAE Paper 982185, 1998
Fuel reduction values [litres/(100kg * 100km)] for passenger cars with different engine types:
Results from a EUCAR survey: low data - as a rule - do not include any change of gear/
axle ratio in connection with a mass reduction, while higher data include these and
additional measurements to keep the previous vehicle performance in combination with a
lower fuel consumption
Average: 0.38, nevertheless the paper suggests to set an average for the FRV to 0.6 for
automotive LCA studies
Quote from paper: “Further controlled practical tests to accepted test parameters are
necessary to qualify this position.”

App. 3-12
Chapter 3: Literature Research
Summary of ICEV Results
Several literature sources deliver general information about the
correlation of weight reduction and fuel reduction
Found results are in a range of 0.3 to 0.7 l/100 km per 100 kg
weight reduction or
in a range of 4.5 % to 6 % fuel reduction per 10 % weight
reduction (papers of aluminium industry included)
Found results provide less information about used boundary
conditions
Extensive study of ika was conducted – result values are up to
0.47 l/100 km per 100 kg weight reduction (average of all is
0.18)

App. 3-13
Chapter 3: Literature Research
Results for HV
Weis s , Hey w ood, Drake et al.
General Motors Corp. et al.
Graham, R., et al.
A n, F., and D. Santini.
A n, F., A . V y as , J. A nders on,
and D. Santini
Hermanc e, D.
A n, F., and Santini, D.
On The Road In 2020
Ev aluation of pos s ible new pas s enger c ars ,
dev eloped and s old in 2020;
Well-to-Wheel Energy Us e and
Greenhous e Gas Emis s ion of
A dv anc ed Fuel/V ehic le Sy s tems North A meric an A naly s is
A naly s is of 15 c onv entional and hy bridiz ed
v ehic les in three parts : w ell-to-tank, tank-tow heel, w ell-to-w heel;
Ev aluation of dif f erent hy brid v ehic les (w ith
Comparing the Benef its and Impac ts A DV ISOR and others ), hy brid v ehic les w ith
of Hy brid Elec tric V ehic le Options
dif f erent mas s es , but als o w ith dif f erent
pow ertrain lay outs pres ented
A s s es s ing Tank-to-Wheel
Comparis on of 4 s tudies as s es s ing adv anc ed
Ef f ic ienc ies of A dv anc ed Tec hnology v ehic le tec hnologies ac c ording to glider and
V ehic les
pow ertrain mas s es , f uel energy us e,
Comparis on of 5 c ommerc ial or prototy pe
Ev aluating Commerc ial and Prototy pe
hy brids ac c ording to f uel benef its and
HEV s
perf ormanc e
New Ef f ic ienc y Bas eline 2004 Toy ota
Pres entation of the Toy ota Prius
Prius
The s hif t f rom c onv entional to hy brid
pow ertrain c an prov ide s ignif ic ant
Mas s Impac ts on Fuel Ec onomies of improv ements in f uel ec onomy w ith little or no
Conv entional v s . Hy brid Elec tric
c hange in mas s ; Onc e the s w itc h to hy brid
V ehic les
pow ertrains has been made, the ef f ec tiv enes s
of mas s reduc tion in improv ing f uel ec onomy
dec reas es

App. 3-14
Chapter 3: Literature Research
Results for HV (selected)
Source: SAE Paper 2004-01-0572: An/Santini: „Mass Impacts on Fuel Economies
of Conventional vs. Hybrid Electric Vehicles“
An/Santini present correlations between fuel economies and vehicle mass for
production HEV with different levels of hybridisation and examine how this
relationship evolves from CV to HEV
A very simplified method using the tractive work formula and drive
Comparison of different CV and HEV vehicles according to mass shows little
influence of hybridisation on vehicle mass (not the same body type for CV
and HEV!)
Shifting from CV to HEV can bring significant improvements in fuel economy
with little or no change in mass
Effectiveness of mass reduction in improving fuel economy will be reduced
once the switch from CV to HEV has been made
When changing vehicle mass for examination of fuel consumption, the engine
is downsized, too, so consumption reduction is partly due to downsizing of
the engine

App. 3-15
Chapter 3: Literature Research
Results for HV (selected)
Source: SAE Paper 2004-01-0572: An/Santini: „Mass Impacts on …”
Calculation of WEVs from the paper:
Prius
Mass [kg]
-10%
1311
+10%
Average
CVs
5.53
6.01
6.51
l/100km
FWD
FHV
3.39
3.64
3.89
4WD
FHV
3.05
3.26
3.47
Weight Elasticity Value
FWD
4WD
CVs
FHV
FHV
0.80
0.69
0.64
0.83
0.82
0.69
0.69
0.64
0.64
Escape
Mass [kg]
-10%
1758
+10%
Average
CVs
9.31
10.11
10.9
l/100km
FWD
FHV
5.3
5.69
6.07
4WD
FHV
4.93
5.26
5.59
Weight Elasticity Value
FWD
4WD
CVs
FHV
FHV
0.79
0.69
0.63
0.78
0.79
0.67
0.68
0.63
0.63
1 lb = 0.453592 kg; 1 MPG = 235.5 l/100km

App. 3-16
Chapter 3: Literature Research
Results for FCV
Journal (J)/
Book (B)
SAE SP-1691
SAE SP-1635
SAE SP-1790
Title
Fuel Cell Power for
Transportation 2002
Fuel Cells and Alternative Fuels/
Energy Systems
Fuel Cells: Technology,
Alternative Fuels, and Fuel
Processing
Year
2002
2001
sifted trough 18 papers - nothing
specific to mass impact
sifted trough 14 papers - nothing
specific to mass impact
2003
sifted trough 7 papers- nothing
specific to mass impact
SAE SP-1741
Fuel Cell Power for
Transportation 2003
2003
sifted trough 31 papers - nothing
specific to mass impact
SAE SP-1589
Fuel Cell Power for
Transportation 2001
2001
sifted trough 16 papers - nothing
specific to mass impact
SAE PT-84
Fuel Cell Technology for Vehicles
2001
sifted trough 30 papers - nothing
specific to mass impact
and many other papers sifted

App. 3-17
Chapter 3: Literature Research
Summary of FCV
All available search engines used
No specific papers/articles found on mass impact on fuel cell
vehicles
Very many papers/articles on fuel cell technology are internally
available and have been scanned (e.g. more than 100 SAE
papers)
Impact of mass changes was investigated in an fka simulation
study for an OEM, report and results are confidential, but mass
impact was investigated and the WEVs for a methanol fuel cell
vehicle resulted to 0.46 for the NEDC and 0.35 for the HYZEM
driving cycle

Appendix for
Chapter 4:
Fundamentals
App. 4-1
Chapter 4: Fundamentals
Powertrain Losses (ICEV)
thermical losses
(emission) 28 - 32%
thermical losses
(cooling) 26 - 32%
idling- and braking
losses 5 - 7%
driving
energy
15 - 18%
accessories
2 - 4%
friction
charge
cycle
8 - 10%
5 - 7%
friction
1 - 2,5%
friction
1 - 2,5%

App. 4-2
Chapter 4: Fundamentals
Examples of Current Parallel Hybrid Systems
The fuel consumptions of parallel hybrids are similar to power split hybrid systems!
Æ paper…
“Parallel, kombiniert oder leistungsverzweigt?
Ein simulationsgestützter Konzeptvergleich!”
Christian Renner, fka
published at “Tag des Hybrids” 4th October 2005 in Aachen
Golf Eco.Power (2004)
Honda Civic IMA (2003)
ika-Inmove (2001)
Diesel 77 kW; EM 15 kW; 3.8 l/100km
Otto 61 kW; EM 6.5 kW; 4,9 l/100km
Otto 55 kW; EM 25 kW; 6.2 l/100km
©
Chapter 4: Fundamentals
Different Hybrid System: Toyota Prius THS II
(2004)
App. 4-3
Engine:
Power Split Hybrid System
1.5 l gasoline engine, 4 cylinder
57 kW @ 5000 rpm
115 Nm @ 4200 rpm
Synchronous AC Motor:
Maximum output: 50 kW, 1200-1540 rpm
Maximum torque: 400 Nm, 0-1200 rpm
NiMH Battery:
6.5 Ah
202 V
©
App. 4-4
Chapter 4: Fundamentals
Different Hybrid System: Toyota Prius THS II
generator
rotational speed
combustion engine
rotational speed
electric-motor
rotational speed
Power Split Device
increase
of
generator
power
sun gear
increase
of engine
power
acceleration
bridge
internal gear

Appendix for
Chapter 5:
Simulation
App. 5-1
Chapter 5: Simulation – Vehicle Analysis
Determination of Weight Reduction (1)
Aim of weight reduction
Determination of weight reduction value of body-in-white (body
structure with closures, fenders) due to substitution of steel
with new high strength steels etc.
Approach
Determination of vehicle weights and body-in-white (BIW)
weights as basic data for:
Sport Utility Vehicles (SUV), Compact Class Vehicles and
Middle-Size Class Vehicles
Substitution of steel with new high strength steels, optimised
design or substitution with other materials in body-in-white
All values are calculated with two assumptions (20 % and 40 %
reduction of BIW-weight in the primary weight saving step)

App. 5-2
Chapter 5: Simulation – Vehicle Analysis
Sport Utility Vehicles (SUV)
SUV (2000 - 2500 kg)
OEM
Model
Engine
Capacity
[cm3]
Engine Power
[kW / PS]
Curb Weight
[kg]
Gross Vehicle
Weight Rating
[kg]
Porsche
Cayenne
V8
4511
250 / 340
2320
3080
Volkswagen
Touareg
V8
4172
228 / 310
2411
2945
BMW
X5
V8
4398
235 / 320
2195
2700
Volvo
XC90
V8
4414
232 / 315
2171
2650
Mercedes
M-Class
V8
4966
225 / 306
2175
2830
Generic Car
-
8 Cylinder
4500
235 / 320
2195
2840

App. 5-3
Chapter 5: Simulation – Vehicle Analysis
Compact Class Vehicles
Compact Class (1200 - 1400 kg)
OEM
Model
Engine
Capacity
[cm3]
Engine Power
[kW / PS]
Curb Weight
[kg]
Gross Vehicle
Weight Rating
[kg]
Volkswagen
Golf V
R4
1598
85 / 115
1271
1770
Opel
Astra
R4
1598
77 / 105
1230
1705
Audi
A3
R4
1598
85 / 115
1225
1785
BMW
1-Series
R4
1596
85 / 115
1280
1705
Ford
Focus
R4
1596
85 / 115
1277
1720
Generic Car
-
4 Cylinder
1600
85 / 115
1260
1740

App. 5-4
Chapter 5: Simulation – Vehicle Analysis
Middle-Sized Class Vehicles
Middle-Sized Class (1500 - 1800 kg)
OEM
Model
Engine
Capacity
[cm3]
Engine Power
[kW / PS]
Curb Weight
[kg]
Gross Vehicle
Weight Rating
[kg]
Audi
A6
V6
3123
188 / 255
1540
2120
Mercedes
E-Class
V6
2996
170 / 231
1650
2175
BMW
5-Series
R6
2996
190 / 258
1565
2050
Volvo
S80
R6 (Bi-Turbo)
2922
200 / 272
1719
2160
Peugeot
607
V6
2946
155 / 211
1719
2144
Generic Car
-
6 Cylinder
3000
181 / 245
1640
2130

App. 5-5
Chapter 5: Simulation – Vehicle Analysis
Determination of Weight Reduction (2)
Calculation Process
Calculating of primary weight saving as 20 % or 40 % of the
BIW-weight
Results are an absolute and a relative value of primary weight
saving
Calculating of secondary weight saving as 30 % of the primary
weight saving which is approximately the reduction used at the
NSB of ThyssenKrupp Stahl *
Results are an absolute and a relative value of secondary
weight saving
* Source: NSB NewSteelBody – Technische Dokumentation, ThyssenKrupp Stahl

App. 5-6
Chapter 5: Simulation – Vehicle Analysis
Procedure for Weight Reduction
Process
Conventional car
Primary weight
reduction
Secondary weight
reduction
Explanation
• Steel unibody
• Constructive measures (e.g. usage of tailored blanks)
• Material measures (e.g. high strength steels)
• Production process optimisation (e.g. hydroforming)
• Effect on vehicle properties (e.g. driving dynamics)
• Resizing: Due to less weight smaller components
sufficient (engine, drivetrain, chassis)
Lightweight car

App. 5-7
Chapter 5: Simulation – Vehicle Analysis
Weight Reduction - Example NSB
Process
Conventional car
Primary weight
reduction
Development of weight reduction
basic weight:
1,393 kg
body weight:
317 kg
primary weight reduction:
77 kg
basic weight: - 7.03 %
27 %
Secondary weight
reduction
Lightweight car
secondary weight reduction:
body weight: -24.29 %
21 kg
basic weight:
1,295 kg
body weight:
240 kg

App. 5-8
Chapter 5: Simulation – Vehicle Analysis
Weight Reduction Results of Generic Cars
SUV (2000 - 2500 kg) Generic Car
Basic Weights
Weight Reduction
Total
Weight Saving
[kg]
Reduced
Curb Weight
[kg]
Ratio Total WS /
Curb Weight [%]
32.4
140.4
2055
6.4
64.8
280.8
1914
12.8
Total
Weight Saving
[kg]
Reduced
Curb Weight
[kg]
Ratio Total WS /
Curb Weight [%]
Secondary
Primary
Ratio Prim. WS /
Weight Saving
Weight Saving
Curb Weight [%]
[kg]
[kg]
Range
Curb Weight
[kg]
Weight Body
Structure with
closures [kg]
Min. WS (-20%)
2195
540
108.0
4.9
Max. WS (-40%)
2195
540
216.0
9.8
Compact Class (1200 - 1400 kg) Generic Car
Basic Weights
Weight Reduction
Secondary
Primary
Ratio Prim. WS /
Weight Saving
Weight Saving
Curb Weight [%]
[kg]
[kg]
Range
Curb Weight
[kg]
Weight Body
Structure with
closures [kg]
Min. WS (-20%)
1260
360
72.0
5.7
21.6
93.6
1166
7.4
Max. WS (-40%)
1260
360
144.0
11.4
43.2
187.2
1073
14.9
Total
Weight Saving
[kg]
Reduced
Curb Weight
[kg]
Ratio Total WS /
Curb Weight [%]
Middle-Sized Class (1500 - 1800 kg) Generic Car
Weight Reduction
Basic Weights
Secondary
Primary
Ratio Prim. WS /
Weight Saving
Weight Saving
Curb Weight [%]
[kg]
[kg]
Range
Curb Weight
[kg]
Weight Body
Structure with
closures [kg]
Min. WS (-20%)
1640
400
80.0
4.9
24.0
104.0
1536
6.3
Max. WS (-40%)
1640
400
160.0
9.8
48.0
208.0
1432
12.7

App. 5-9
Chapter 5: Simulation – Approach
Driving Resistance Power
Base equation of vehicle longitudinal dynamic:
Pdem = m ⋅ g ⋅ fR ⋅ v + m ⋅ g ⋅ p ⋅ v + (ei ⋅ m veh + mload ) ⋅ a ⋅ v + c d ⋅ A ⋅
ρair 3
⋅v
2
m: vehicle total weight (m = mveh + mload)
g: acceleration of gravity
fR: road resistance factor
v: vehicle speed
p: ascending coefficient
ei: mass factor
vehicle empty weight
mVeh:
mass of payload
mload:
a: vehicle acceleration
cd: air drag coefficient
A: vehicle face surface
ρair: density of air
source: ika

dr
ag
g
br
id
si
br
ak
e
br
ak
in
co
g
m
po
ne
nt
s
ne
on
ch
an
ce
si
ut
is
st
m
el
re
he
en
gi
w
ro
l lin
ns
cl
1500
hy
&
tra
en
gi
ne
au
xi
l ia
rie
s
Specific Loss Energy [kJ/km]
App. 5-10
Chapter 5: Simulation – Approach
Powertrain Losses (Example SUV at NEDC)
2500
2000
conventional
hybrid
1000
500
0

App. 5-11
Chapter 5: Simulation – Approach
Longitudinal Vehicle Models in Matlab®/Simulink®
The used Matlab®/Simulink® models are dynamical models of
the powertrains and vehicles, which provide an allocation of the
second by second energy flows. The model can be used for
Prediction of consumption and driving performance
Comparison of vehicle and powertrain concepts
Design of the control algorithm
Transfer of the control strategy by automatic code
generation
Modular architecture of the models
Modelling according to the principle of cause and effect
(Bond Graph Principle)

Chapter 5: Simulation – Approach
MATLAB®/Simulink® - Standard Simulation Tool
in the Automotive Industry
App. 5-12

Chapter 5: Simulation – Approach
Representation of the
Drivetrain Components in Maps and Equations
App. 5-13
∫
V = a x dt
ax =
Fdem − FZ ⋅ (p + fR ) + c w ⋅ A ⋅
(e i ⋅ m F + m Zu )
ρL 2
⋅v
2

App. 5-14
Chapter 5: Simulation – Approach
Example Component Model Module
“Mapped Inline Electric Motor“

App. 5-15
Chapter 5: Simulation – Approach
Example for the necessary input data
Pdem
Tdem
PFC
control
unit
a=
driver and cycle
F
auxiliaries
fuel cell power plant
I
H2
U
air
I
fuel cell
vveh
electrical
circuit
I
∫
V = ax
U
U
U
T
I
N
electric motor
T
transmission
N
v
vehicle longitudinal
dynamics
ax =
Fdem − FZ ⋅ (p + fR ) + c w ⋅ A ⋅
(e i ⋅ m F + m Zu )
ρL 2
⋅v
2
battery

App. 5-16
Chapter 5: Simulation – Approach
Vehicle Architectures (Examples)
Anode
conventional
vehicle
parallelhybrid
fuel cell
vehicle

App. 5-17
Chapter 5: Simulation – Approach
Used Cycles: NEDC
120
100
Standard synthetic cycle
for consumption
measurement in Europe
Maximum acceleration
is low:
1.04 m/s²
Average speed is low:
33.2 km/h
speed [km/h]
80
60
40
20
0
0
200
400
600
time [s]
800
1000
1200

App. 5-18
Chapter 5: Simulation – Approach
Used Cycles: HYZEM
140
120
Common cycle
representing real world
traffic
Nearly similar to
FTP75 cycle
Maximum acceleration
is high:
3.1 m/s² (peak)
Average speed is high:
68.36 km/h
speed [km/h]
100
80
60
40
20
0
0
500
1000
1500
2000
time [s]
2500
3000
3500

Chapter 5: Simulation – Approach
Time Record of Vehicle Parameters
(Hybrid Vehicle)
velocity [km/h]
App. 5-19
100
50
0
1800
1850
1900
1950
2000
2050
2100
2150
2200
2250
2300
2350
2500
1500
1000
EM
ICE
500
0
1800
1850
1900
1950
2000
2050
2100
2150
2200
2250
2300
2350
1800
1850
1900
1950
2000
2050
time [s]
2100
2150
2200
2250
2300
2350
4
fuelrate [g/s]
speed [rpm]
2000
3
2
1
0

App. 5-20
Chapter 5: Simulation – Approach
Adaptation of Engine Power
1. Determination of acceleration figures of the basic vehicle (Generic Car, 85 kW)
2. Reduction of vehicle weight (Min / Max Weight Saving)
3. Reduction of engine power so that acceleration figures of lightweight vehicle and
basic vehicle correspond
Generic Car
Min WS
Max WS
Min WS
Max WS
(85 kW)
(85 kW)
(85 kW)
(79 kW)
(74 kW)
[s]
[s]
[s]
[s]
[s]
0-50 km/h
3.5
3.3
3.1
3.5
3.4
0-80 km/h
6.5
6.1
5.7
6.5
6.4
0-100 km/h
9.8
9.2
8.5
9.9
9.8
0-130 km/h
16.2
15.0
13.9
16.3
16.3
(example: Compact Class)

Chapter 5: Simulation – Approach
Longitudinal Model of a parallel Hybrid Vehicle
(Matlab®/Simulink®)
App. 5-21
co ntro l
EngOut
v
wtra ns
C lutc h1Out
tra ns m _loc ke d
c lutc h2_loc ke d
Em Out
we m
c lutc h1_loc ke d
C lutc h2Out
we ng
Tic e
Tra Out
s oc
v olta ge
Ve hOut
Tdemand
C onin
wout
F bkin
e ng_trq
Ma p p e d Inte rn a l
Com b u stion En gine
(with se p e ra te
id le fue l co n su m ptio n)
Fn
locked_f lag
win
wout
Fbkin
Fbkout
Friction Clutch 1
P
C onin
win
Fbkin
wout
Fn
loc ke d_f la g
win
wout
F bkin
Voltage Fbkout
F bkout
Frictio n Clu tch 2
Mapped Inline
Electric Motor
win
F bkin
loc ke d_f la g
wout
F bkout
S ix S p e e d
Tra nsm issio n
Tbra ke
v
w
F bkin
F bkout
Ve hicle
Ut
P
s oc
-CSum
a u xilia r po we r
NiMH-Ba tte ry

App. 5-22
Chapter 5: Simulation – Approach
FCV Model in Matlab®/Simulink®
FUEL CELL VEHICLE
Pure Hydrogen
Hybrid System
Global Settings
Ambient Pressure: 101325 Pa
Ambient Temperature: 293 K
Ambient Humidity: 45 %
Record Step Time: 0.1 s
Simulation Step Time: 0.01 s
Solver: ode4
Eta t_sim
Driver and Cycle Model
Step (s): Var=0.1, Sim=0.01
Stack always functioning
1 x HyZEM (3207s)
Ene rgy Flows
Global_Settings
C trl_F C
[S ta te _F C ]
C trl_Ba t
I_F C
Displa y4
U_F C
FIG.FC.U
IC
P owe r P la nt
0
C trl_Aux
C trl_EM
C_Hydroge n
I_C om p
C trl_Ve h
U_C om p
C trl_EA
Ctrl_H2Tank
Ctrl_Comp
IC2
[0]
I_EM
U_EM
I_F C
U_Ba t
I_C om p
Ele ctrica l
U_F C
Ne twork
I_Ba t
Archite cture
I_AuxVe h
Battery
-20 kW < P < 20 kW
SOC ini = %
IC1
[0]
U_C om p
[S ta te _Ba t]
Ve hicle
Control
Unit
P m in_Aux :
600W
S ta ck pre ssure controlle d with :
curre nt de nsity
Ctrl_Water_Tank
[S ta te _Aux]
[S ta te _EM]
[S ta te _Ve h]
[S ta te _EA]
[State_Comp]
[State_H2Tank]
[State_Water_Tan
Ctrl_CS
[State_CS]
Ctrl_PP
[State_PP]
Displa y2
0
U_AuxVe h
Electric Motor
Reduction Gear
Vehicle Golf
Vehicle Auxiliairies
Cooling S yste m
Displa y1
0
Hybrid fuel cell system

Chapter 5: Simulation – Approach
Time Record of Vehicle Parameters
(Fuel Cell Vehicle)
App. 5-23
velocity [km/h]
150
100
50
0
0
40
30
power [kW]
VDC
VVeh
20
200
400
600
time [s]
800
1000
1200
400
600
time [s]
800
1000
1200
PFC
PEM
PBat
10
0
-10
-20
0
200

App. 5-24
Chapter 5: Simulation – Approach
Configuration of a Fuel Cell Vehicle
(Hybrid) Model
Pdem
Tdem
PFC
control
unit
vveh
driver and cycle
auxiliaries
fuel cell power plant
I
H2
U
air
I
fuel cell
U
electrical
circuit
I
U
T
I
N
electric motor
T
transmission
N
v
vehicle longitudinal
dynamics
U
battery

App. 5-25
1
Chapter 5: Simulation – Approach
Example Component Model Module
“Mapped Inline Electric Motor“
Tde m a nd
Tde m a nd
w
4
Control Unit
T
Tm ot
v olta ge
w
P
Volta ge
1
P
Torque
v olta ge
Ele ctric P owe r
De m a nd
T
wout
2
win
wout
win
3
Fbkin
F bkin
2
F bkout
3
Fbkout
Me cha nics

App. 5-26
Chapter 5: Simulation – Results
Principle of ICEV

App. 5-27
Chapter 5: Simulation – Results
ICEV-G Data in Simulation
Generic Car
Compact
Class
Generic Car
Middle-Sized
Class
Generic Car
SUV
Vehicle Weight
[kg]
1260
1640
2195
Engine Power
[kW]
85
181
235
[-]
0.31
0.27
0.36
[m²]
2.16
2.24
2.78
CD
A

App. 5-28
Chapter 5: Simulation – Results
ICEV-D Data in Simulation
Generic Car
Compact
Class
Generic Car
Middle-Sized
Class
Generic Car
SUV
Vehicle Weigh
[kg]
1350
1740
2320
Engine Power
[kW]
100
170
220
[-]
0.31
0.27
0.36
[m²]
2.16
2.24
2.78
CD
A

App. 5-29
Chapter 5: Simulation – Results
Principle of HV

App. 5-30
Chapter 5: Simulation – Results
HV-G Data in Simulation
Generic Car
Compact
Class
Generic Car
Middle-Sized
Class
Generic Car
SUV
Vehicle Weight
[kg]
1335
1752
2345
Engine Power
[kW]
85
181
235
Motor Power
[kW]
20
30
40
[-]
0.31
0.27
0.36
[m²]
2.16
2.24
2.78
CD
A
ICE same power as conventional vehicle
Electric motor sized to enable regenerative breaking and
partial electric propulsion

App. 5-31
Chapter 5: Simulation – Results
HV-D Data in Simulation
Generic Car
Compact
Class
Generic Car
Middle-Sized
Class
Generic Car
SUV
Vehicle Weight
[kg]
1425
1852
2470
Engine Power
[kW]
100
170
220
Motor Power
[kW]
20
30
40
[-]
0.31
0.27
0.36
[m²]
2.16
2.24
2.78
CD
A
ICE same power as conventional vehicle
Electric motor sized to enable regenerative breaking and
partial electric propulsion

App. 5-32
Chapter 5: Simulation – Results
Principle of FCV

App. 5-33
Chapter 5: Simulation – Results
FCV Data in Simulation
Generic Car
Generic Car
Middle-Sized
Compact Class
Class
[kg]
1335
1752
[kg]
1241 (-94)
1648 (-104)
[kg] 1148 (-187)
1544 (-208)
Vehicle Weight
Min WS
Max WS
Electric Motor
[kW]
Peak Power
CD
[-]
A
[m²]
0 to 100 km/h
[s]
Generic Car
SUV
2345
2205 (-140)
2065 (-181)
64-73
116-131
173-194
0.3
2.2
9.8
0.3
2.2
6.9
0.4
2.8
6.5
Electric motor sized to enable same acceleration as the ICEV
Fuel cell system sized to provide the electric motor with the maximum
continuous power, during full acceleration additional power is provided by
the battery
Acceleration 0 to 100 km/h is calculated for the curb weight without any
payload (catalogue data is measured for ½ max. payload)

App. 5-34
Chapter 5: Simulation – Results
10 % Weight Reduction, NEDC
Compact Class
Mid-Size Class
SUV
-1.9
-2.6
-3.5
-3.1
-2.4
-2.7
-2.6
-2.9
-3.6
-3.9
-4.5
-4.9 -4.9
-5.3
-4.9
-5.7
-5.1
-5.8
-6.0 -5.9
-6.3
-6.8
-7.0
-7.1
-8.2
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
-7.9
-7.7
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain
-4.7
-7.4
-7.1
in [%]

App. 5-35
Chapter 5: Simulation – Results
10 % Weight Reduction, NEDC
Compact Class
Mid-Size Class
SUV
-0.11
-0.17 -0.18 -0.18
-0.13
-0.14
-0.18
-0.17 -0.15
-0.19
-0.18 -0.20
-0.20
-0.27 -0.26
-0.26 -0.26
-0.36
-0.34
-0.32
-0.42
-0.31
-0.45
-0.48
-0.24
-0.42
-0.59
-0.69
-0.79
-1.02
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain
in [l/100km]

App. 5-36
Chapter 5: Simulation – Results
10 % Weight Reduction, HYZEM
Compact Class
-3.1
-3.4
-3.2
Mid-Size Class
-3.0
-3.4
SUV
-3.0
-3.2 -3.4
-3.2 -3.4 -3.3
-3.8
-4.2
-4.9 -4.8-4.9
-5.4
-5.5 -5.5
-5.0
-5.1
-5.9
-6.8
-5.5
-5.7 -5.6
-4.6
-4.6
-5.2
-6.6
in [%]
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain

App. 5-37
Chapter 5: Simulation – Results
10 % Weight Reduction, HYZEM
Compact Class
Mid-Size Class
SUV
-0.11
-0.20
-0.17
-0.16
-0.19
-0.17
-0.21
-0.22
-0.21
-0.18
-0.18
-0.23
-0.23
-0.26
-0.30
-0.35
-0.31
-0.37
-0.28
-0.29
-0.33
-0.35
-0.40 -0.40
-0.37
-0.44
-0.51
-0.55
-0.60
-0.66
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain
in [l/100km]

App. 5-38
Chapter 5: Simulation – Results
100 kg Weight Reduction, NEDC
Compact Class
Mid-Size Class
SUV
-1.1 -1.1 -1.2
-1.2
-1.6
-2.1
-2.6
-2.8
-3.1
-4.1
-1.8
-2.0
-2.0
-1.9
-2.1
-3.4 -3.5
-2.8
-3.8
-4.0
-2.5 -2.6
-3.6
-3.3
-3.0
-4.2
-4.6
-5.5
-5.2
-5.1
in [%]
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain

App. 5-39
Chapter 5: Simulation – Results
100 kg Weight Reduction, NEDC
Compact Class
Mid-Size Class
-0.08
-0.13 -0.13 -0.14
-0.10
-0.11
-0.12
-0.08
-0.09 -0.09
-0.11
-0.12 -0.12
-0.17
-0.19
SUV
-0.11 -0.10 -0.12
-0.15
-0.11
-0.18 -0.17
-0.18
-0.26
-0.27
-0.29
-0.34
-0.35
-0.45
-0.50
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain
in [l/100km]

App. 5-40
Chapter 5: Simulation – Results
100 kg Weight Reduction, HYZEM
Compact Class
Mid-Size Class
SUV
-1.4 -1.4 -1.5 -1.3
-2.1
-2.0
-1.9
-2.3
-2.5 -2.5 -2.4 -2.4
-3.6
-2.7
-3.4
-3.7
-4.0
-4.4
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
-2.1
-2.7
-2.9
-3.2
-2.5
-2.4 -2.3
-2.0
-2.1 -2.0
-3.8
-4.2
in [%]
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain

App. 5-41
Chapter 5: Simulation – Results
100 kg Weight Reduction, HYZEM
Compact Class
Mid-Size Class
SUV
-0.07
-0.11
-0.13
-0.16
-0.15
-0.12
-0.13
-0.16
-0.16
-0.12
-0.17
-0.20
-0.10
-0.10
-0.18
-0.11
-0.10
-0.10
-0.13
-0.16
-0.16
-0.18
-0.20
-0.22
-0.22
-0.23
-0.25
-0.28
-0.30
-0.34
in [l/100km]
ICEV-G base powertrain
ICEV-D base powertrain
HV-G base powertrain
HV-D base powertrain
FC base powertrain
ICEV-G re-sized powertrain
ICEV-D re-sized powertrain
HV-G re-sized powertrain
HV-D re-sized powertrain
FC re-sized powertrain

App. 5-42
Chapter 5: Simulation – Results
Weight Elasticity Values ICEV-G, NEDC
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Fuel Consumption
Vehicle Weight
Weight
Saving
Engine
Power
[kW]
-
85
6.27
-
0.0
1260
-
0.0
-
Min WS
85
6.14
0.12
2.0
1166
94
7.5
0.27
Max WS
85
6.02
0.24
3.9
1073
187
14.8
0.26
Min WS
79
5.94
0.32
5.2
1166
94
7.5
0.69
Max WS
74
5.65
0.61
9.8
1073
187
14.8
0.66
-
181
9.66
-
0.0
1640
-
0.0
-
Min WS
181
9.54
0.12
1.3
1536
104
6.3
0.20
Max WS
181
9.43
0.23
2.4
1432
208
12.7
0.19
Min WS
170
9.15
0.52
5.3
1536
104
6.3
0.84
Max WS
160
8.67
1.00
10.3
1432
208
12.7
0.81
-
235
13.69
-
0.0
2195
-
0.0
-
Min WS
235
13.48
0.21
1.6
2055
140
6.4
0.25
Max WS
235
13.29
0.41
3.0
1914
281
12.8
0.23
Min WS
222
13.07
0.63
4.6
2055
140
6.4
0.72
Max WS
207
12.38
1.32
9.6
1914
281
12.8
0.75
absolute
[l/100km]
Reduction Reduction
[l/100km]
[%]
absolute
[kg]
Reduction Reduction
[kg]
[%]
WEV

App. 5-43
Chapter 5: Simulation – Results
Weight Elasticity Values ICEV-G, HYZEM
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Fuel Consumption
Vehicle Weight
Weight
Saving
Engine
Power
[kW]
-
85
6.40
-
0.0
1260
-
0.0
-
Min WS
85
6.25
0.15
2.3
1166
94
7.5
0.31
Max WS
85
6.11
0.29
4.5
1073
187
14.8
0.30
Min WS
79
6.13
0.27
4.2
1166
94
7.5
0.56
Max WS
74
5.87
0.52
8.1
1073
187
14.8
0.55
-
181
8.07
-
0.0
1640
-
0.0
-
Min WS
181
7.90
0.17
2.1
1536
104
6.3
0.33
Max WS
181
7.74
0.33
4.1
1432
208
12.7
0.32
Min WS
170
7.71
0.35
4.4
1536
104
6.3
0.69
Max WS
160
7.37
0.70
8.6
1432
208
12.7
0.68
-
235
11.59
-
0.0
2195
-
0.0
-
Min WS
235
11.36
0.23
2.0
2055
140
6.4
0.31
Max WS
235
11.14
0.45
3.8
1914
281
12.8
0.30
Min WS
222
11.17
0.41
3.6
2055
140
6.4
0.56
Max WS
207
10.74
0.85
7.3
1914
281
12.8
0.57
absolute
[l/100km]
Reduction Reduction
[l/100km]
[%]
absolute
[kg]
Reduction Reduction
[kg]
[%]
WEV

App. 5-44
Chapter 5: Simulation – Results
Weight Elasticity Values ICEV-D, NEDC
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Engine
Weight
Power
Saving
[kW]
Fuel Consumption
Vehicle Weight
absolute Reduction Reduction absolute Reduction Reduction
[kg]
[kg]
[%]
[l/100km] [l/100km]
[%]
WEV
-
100
5.13
-
0.0
1350
-
0.0
-
Min WS
100
5.00
0.12
2.4
1256
94
7.0
0.35
Max WS
100
4.88
0.25
4.8
1163
187
13.9
0.35
Min WS
94
4.88
0.25
4.9
1256
94
7.0
0.71
Max WS
87
4.62
0.51
9.9
1163
187
13.9
0.71
-
170
7.50
-
0.0
1740
-
0.0
-
Min WS
170
7.37
0.13
1.8
1636
104
6.0
0.29
Max WS
170
7.26
0.24
3.2
1532
208
12.0
0.27
Min WS
161
7.14
0.36
4.8
1636
104
6.0
0.81
Max WS
152
6.80
0.71
9.4
1532
208
12.0
0.79
-
220
9.72
-
0.0
2320
-
0.0
-
Min WS
220
9.56
0.16
1.6
2180
140
6.1
0.27
Max WS
220
9.41
0.31
3.2
2039
281
12.1
0.26
Min WS
209
9.31
0.40
4.2
2180
140
6.1
0.69
Max WS
197
8.89
0.83
8.5
2039
281
12.1
0.71

App. 5-45
Chapter 5: Simulation – Results
Weight Elasticity Values ICEV-D, HYZEM
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Engine
Weight
Power
Saving
[kW]
Fuel Consumption
Vehicle Weight
absolute Reduction Reduction absolute Reduction Reduction
[kg]
[%]
[l/100km] [l/100km]
[%]
[kg]
WEV
-
100
4.93
-
0.0
1350
-
0.0
-
Min WS
100
4.81
0.12
2.4
1256
94
7.0
0.35
Max WS
100
4.70
0.23
4.7
1163
187
13.9
0.34
Min WS
94
4.75
0.18
3.7
1256
94
7.0
0.54
Max WS
87
4.55
0.38
7.7
1163
187
13.9
0.55
-
170
6.15
-
0.0
1740
-
0.0
-
Min WS
170
6.03
0.12
2.0
1636
104
6.0
0.33
Max WS
170
5.90
0.25
4.0
1532
208
12.0
0.34
Min WS
161
5.90
0.24
4.0
1636
104
6.0
0.66
Max WS
152
5.67
0.48
7.8
1532
208
12.0
0.66
-
220
9.13
-
0.0
2320
-
0.0
-
Min WS
220
8.95
0.18
2.0
2180
140
6.1
0.33
Max WS
220
8.77
0.36
3.9
2039
281
12.1
0.32
Min WS
209
8.83
0.30
3.3
2180
140
6.1
0.55
Max WS
197
8.51
0.62
6.8
2039
281
12.1
0.56

App. 5-46
Chapter 5: Simulation – Results
Weight Elasticity Values HV-G, NEDC
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Fuel Consumption
Vehicle Weight
Weight
Saving
Engine
Power
[kW]
Motor
Power
[kW]
-
85
20
4.52
-
0.0
1335
-
0.0
-
Min WS
85
20
4.39
0.13
2.9
1241
94
7.0
0.42
Max WS
85
20
4.28
0.24
5.3
1148
187
14.0
0.37
Min WS
80
19
4.35
0.17
3.9
1241
94
7.0
0.55
Max WS
75
18
4.15
0.37
8.2
1148
187
14.0
0.58
-
181
30
6.23
-
0.0
1752
-
0.0
-
Min WS
181
30
6.05
0.18
2.9
1648
104
5.9
0.48
Max WS
181
30
5.78
0.45
7.2
1544
208
11.9
0.61
Min WS
172
29
5.96
0.27
4.4
1648
104
5.9
0.74
Max WS
161
27
5.66
0.57
9.2
1544
208
11.9
0.78
-
235
40
8.90
-
0.0
2345
-
0.0
-
Min WS
235
40
8.75
0.15
1.6
2205
140
6.0
0.28
Max WS
235
40
8.58
0.31
3.5
2064
281
12.0
0.29
Min WS
223
38
8.65
0.25
2.8
2205
140
6.0
0.47
Max WS
212
36
8.34
0.56
6.2
2064
281
12.0
0.52
absolute
[l/100km]
Reduction Reduction
[l/100km]
[%]
absolute
[kg]
Reduction Reduction
[kg]
[%]
WEV

App. 5-47
Chapter 5: Simulation – Results
Weight Elasticity Values HV-G, HYZEM
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Vehicle Weight
Fuel Consumption
Weight
Saving
Engine
Power
[kW]
Motor
Power
[kW]
-
85
20
6.12
-
0.0
1335
-
0.0
-
Min WS
85
20
5.99
0.14
2.3
1241
94
7.0
0.32
Max WS
85
20
5.85
0.27
4.4
1148
187
14.0
0.32
Min WS
80
19
5.92
0.21
3.4
1241
94
7.0
0.48
Max WS
75
18
5.69
0.43
7.0
1148
187
14.0
0.50
-
181
30
7.33
-
0.0
1752
-
0.0
-
Min WS
181
30
7.15
0.18
2.4
1648
104
5.9
0.40
Max WS
181
30
6.96
0.37
5.1
1544
208
11.9
0.43
Min WS
172
29
7.12
0.21
2.8
1648
104
5.9
0.48
Max WS
161
27
6.84
0.49
6.6
1544
208
11.9
0.56
-
235
40
10.92
-
0.0
2345
-
0.0
-
Min WS
235
40
10.70
0.22
2.0
2205
140
6.0
0.34
Max WS
235
40
10.49
0.44
4.0
2064
281
12.0
0.33
Min WS
223
38
10.57
0.35
3.2
2205
140
6.0
0.54
Max WS
212
36
10.21
0.72
6.6
2064
281
12.0
0.55
absolute
[l/100km]
Reduction Reduction
[%]
[l/100km]
absolute
[kg]
Reduction Reduction
[%]
[kg]
WEV

App. 5-48
Chapter 5: Simulation – Results
Weight Elasticity Values HV-D, NEDC
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Engine
Weight
Power
Saving
[kW]
Motor
Power
[kW]
Vehicle Weight
Fuel Consumption
absolute Reduction Reduction absolute Reduction Reduction
[kg]
[kg]
[%]
[l/100km] [l/100km]
[%]
WEV
-
100
20
3.70
-
0.0
1425
-
0.0
-
Min WS
100
20
3.63
0.07
1.9
1331
94
6.6
0.29
Max WS
100
20
3.55
0.15
4.1
1238
187
13.1
0.31
Min WS
94
19
3.58
0.12
3.2
1331
94
6.6
0.48
Max WS
89
18
3.46
0.24
6.4
1238
187
13.1
0.49
-
170
30
4.80
-
0.0
1852
-
0.0
-
Min WS
170
30
4.70
0.09
1.9
1748
104
5.6
0.35
Max WS
170
30
4.60
0.19
4.0
1644
208
11.2
0.36
Min WS
161
28
4.60
0.19
4.0
1748
104
5.6
0.72
Max WS
155
27
4.43
0.37
7.6
1644
208
11.2
0.68
-
220
40
7.01
-
0.0
2470
-
0.0
-
Min WS
220
40
6.84
0.17
2.5
2330
140
5.7
0.44
Max WS
220
40
6.65
0.36
5.1
2189
281
11.4
0.45
Min WS
209
38
6.77
0.24
3.5
2330
140
5.7
0.61
Max WS
198
36
6.53
0.48
6.9
2189
281
11.4
0.60

App. 5-49
Chapter 5: Simulation – Results
Weight Elasticity Values HV-D, HYZEM
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Engine
Weight
Power
Saving
[kW]
Motor
Power
[kW]
Fuel Consumption
Vehicle Weight
absolute Reduction Reduction absolute Reduction Reduction
[l/100km] [l/100km]
[%]
[kg]
[kg]
[%]
WEV
-
100
20
4.59
-
0.0
1425
-
0.0
-
Min WS
100
20
4.49
0.10
2.3
1331
94
6.6
0.34
Max WS
100
20
4.39
0.20
4.4
1238
187
13.1
0.34
Min WS
94
19
4.44
0.15
3.2
1331
94
6.6
0.49
Max WS
89
18
4.30
0.29
6.3
1238
187
13.1
0.48
-
170
30
5.62
-
0.0
1852
-
0.0
-
Min WS
170
30
5.49
0.12
2.2
1748
104
5.6
0.39
Max WS
170
30
5.38
0.24
4.2
1644
208
11.2
0.38
Min WS
161
28
5.43
0.19
3.4
1748
104
5.6
0.60
Max WS
155
27
5.26
0.36
6.5
1644
208
11.2
0.58
-
220
40
8.57
-
0.0
2470
-
0.0
-
Min WS
220
40
8.42
0.15
1.8
2330
140
5.7
0.31
Max WS
220
40
8.24
0.33
3.8
2189
281
11.4
0.34
Min WS
209
38
8.33
0.24
2.8
2330
140
5.7
0.50
Max WS
198
36
8.05
0.52
6.0
2189
281
11.4
0.53

App. 5-50
Chapter 5: Simulation – Results
Weight Elasticity Values FCV, NEDC
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Fuel Consumption
Vehicle Weight
Weight
Saving
Motor
Power
[kW]
-
73
2.71
-
0.0
1335
-
0.0
-
Min WS
73
2.61
0.10
3.8
1241
1241
7.0
0.53
Max WS
73
2.51
0.20
7.3
1148
1148
14.0
0.52
Min WS
68
2.62
0.09
3.3
1241
1241
7.0
0.47
Max WS
64
2.52
0.19
7.0
1148
1148
14.0
0.50
-
131
3.06
-
0.0
1752
-
0.0
-
Min WS
131
2.97
0.09
3.0
1648
104
5.9
0.50
Max WS
131
2.88
0.18
5.8
1544
208
11.9
0.49
Min WS
123
2.95
0.11
3.7
1648
104
5.9
0.62
Max WS
116
2.83
0.23
7.6
1544
208
11.9
0.64
-
194
4.15
-
0.0
2345
-
0.0
-
Min WS
194
4.04
0.12
2.9
2205
140
6.0
0.48
Max WS
194
3.92
0.24
5.7
2064
281
12.0
0.47
Min WS
184
4.00
0.15
3.7
2205
140
6.0
0.62
Max WS
173
3.86
0.29
7.1
2064
281
12.0
0.59
absolute
[l/100km]
Reduction Reduction
[l/100km]
[%]
absolute
[kg]
Reduction Reduction
[kg]
[%]
results in gasoline equivalent: LHV of gasoline 42500 kJ/kg, density: 0.75 kg/l
WEV

App. 5-51
Chapter 5: Simulation – Results
Weight Elasticity Values FCV, HYZEM
Vehicle Class
Compact
Class
Middle-Sized
Car
SUV
Fuel Consumption
Vehicle Weight
Weight
Saving
Motor
Power
[kW]
-
73
3.52
-
0.0
1335
-
0.0
-
Min WS
73
3.40
0.12
3.5
1241
94
7.0
0.50
Max WS
73
3.28
0.24
6.9
1148
187
14.0
0.49
Min WS
68
3.46
0.07
2.0
1241
94
7.0
0.28
Max WS
64
3.37
0.15
4.4
1148
187
14.0
0.31
-
131
3.54
-
0.0
1752
-
0.0
-
Min WS
131
3.43
0.11
3.0
1648
104
5.9
0.51
Max WS
131
3.33
0.21
6.0
1544
208
11.9
0.51
Min WS
123
3.44
0.10
2.8
1648
104
5.9
0.48
Max WS
116
3.33
0.21
6.0
1544
208
11.9
0.50
-
194
5.09
-
0.0
2345
-
0.0
-
Min WS
194
4.95
0.14
2.8
2205
140
6.0
0.46
Max WS
194
4.81
0.28
5.5
2064
281
12.0
0.46
Min WS
184
4.94
0.15
2.9
2205
140
6.0
0.48
Max WS
173
4.81
0.28
5.4
2064
281
12.0
0.45
absolute
[l/100km]
Reduction Reduction
[l/100km]
[%]
absolute
[kg]
Reduction Reduction
[%]
[kg]
results in gasoline equivalent: LHV of gasoline 42500 kJ/kg, density: 0.75 kg/l
WEV

App. 5-52
Vehicle Class
Chapter 5: Simulation – Results
Overview of all WEVs
NEDC
ICEV-G
NEDC
ICEV-D
NEDC
HV-G
NEDC
HV-D
NEDC
FC
HYZEM
ICEV-G
HYZEM
ICEV-D
HYZEM
HV-G
HYZEM
HV-D
HYZEM
FC
same as base
0.27
0.35
0.42
0.29
0.53
0.31
0.35
0.32
0.34
0.50
Max WS same as base
0.26
0.35
0.37
0.31
0.52
0.30
0.34
0.32
0.34
0.49
Min WS
re-sized 1
0.69
0.71
0.55
0.48
0.47
0.56
0.54
0.48
0.49
0.28
Max WS
re-sized 2
0.66
0.71
0.58
0.49
0.50
0.55
0.55
0.50
0.48
0.31
Min WS
same as base
0.20
0.29
0.48
0.35
0.50
0.33
0.33
0.40
0.39
0.51
Max WS same as base
0.19
0.27
0.61
0.36
0.49
0.32
0.34
0.43
0.38
0.51
Min WS
re-sized 1
0.84
0.81
0.74
0.72
0.61
0.69
0.66
0.48
0.60
0.48
Max WS
re-sized 2
0.81
0.79
0.78
0.68
0.63
0.68
0.66
0.56
0.58
0.50
Min WS
same as base
0.25
0.27
0.28
0.44
0.48
0.31
0.33
0.34
0.31
0.46
Max WS same as base
0.23
0.26
0.29
0.45
0.47
0.30
0.32
0.33
0.34
0.46
Min WS
re-sized 1
0.72
0.69
0.47
0.61
0.61
0.56
0.55
0.54
0.50
0.48
Max WS
re-sized 2
0.75
0.71
0.52
0.60
0.58
0.57
0.56
0.55
0.53
0.45
Weight Engine Power
Saving
[kW]
Min WS
Compact
Class Car
Middle-Sized
Car
SUV

Chapter 5: Simulation – Results
Overview of all Powertrain Technologies in the
Compact Class, NEDC
App. 5-53
Fuel Consumption
Powertrain
Technology
ICEV-G
ICEV-D
HV-G
HV-D
Fuel Cell
Vehicle Weight
Weight Engine / Motor
absolute Reduction Reduction absolute Reduction Reduction
Power
Saving
[l/100km] [l/100km]
[%]
[kg]
[kg]
[%]
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
6.27
6.14
6.02
5.94
5.65
5.13
5.00
4.88
4.88
4.62
4.52
4.39
4.28
4.35
4.15
3.70
3.63
3.55
3.58
3.46
2.71
2.61
2.51
2.62
2.52
0.12
0.24
0.32
0.61
0.12
0.25
0.25
0.51
0.13
0.24
0.17
0.37
0.07
0.15
0.12
0.24
0.10
0.20
0.09
0.19
0.0
2.0
3.9
5.2
9.8
0.0
2.4
4.8
4.9
9.9
0.0
2.9
5.3
3.9
8.2
0.0
1.9
4.1
3.2
6.4
0.0
3.8
7.3
3.3
7.0
1260
1166
1073
1166
1073
1350
1256
1163
1256
1163
1335
1241
1148
1241
1148
1425
1331
1238
1331
1238
1335
1241
1148
1241
1148
94
187
94
187
94
187
94
187
94
187
94
187
94
187
94
187
94
187
94
187
0.0
7.5
14.8
7.5
14.8
0.0
7.0
13.9
7.0
13.9
0.0
7.0
14.0
7.0
14.0
0.0
6.6
13.1
6.6
13.1
0.0
7.0
14.0
7.0
14.0
WEV
0.27
0.26
0.69
0.66
0.35
0.35
0.71
0.71
0.42
0.37
0.55
0.58
0.29
0.31
0.48
0.49
0.53
0.52
0.47
0.50

Chapter 5: Simulation – Results
Overview of all Powertrain Technologies in the
Compact Class, HYZEM
App. 5-54
Fuel Consumption
Powertrain
Technology
ICEV-G
ICEV-D
HV-G
HV-D
Fuel Cell
Vehicle Weight
Weight Engine / Motor
absolute Reduction Reduction absolute Reduction Reduction
Power
Saving
[l/100km] [l/100km]
[%]
[kg]
[kg]
[%]
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
6.40
6.25
6.11
6.13
5.87
4.93
4.81
4.70
4.75
4.55
6.12
5.99
5.85
5.92
5.69
4.59
4.49
4.39
4.44
4.30
3.52
3.40
3.28
3.46
3.37
0.15
0.29
0.27
0.52
0.12
0.23
0.18
0.38
0.14
0.27
0.21
0.43
0.10
0.20
0.15
0.29
0.12
0.24
0.07
0.15
0.0
2.3
4.5
4.2
8.1
0.0
2.4
4.7
3.7
7.7
0.0
2.3
4.4
3.4
7.0
0.0
2.3
4.4
3.2
6.3
0.0
3.5
6.9
2.0
4.4
1260
1166
1073
1166
1073
1350
1256
1163
1256
1163
1335
1241
1148
1241
1148
1425
1331
1238
1331
1238
1335
1241
1148
1241
1148
94
187
94
187
94
187
94
187
94
187
94
187
94
187
94
187
94
187
94
187
0.0
7.5
14.8
7.5
14.8
0.0
7.0
13.9
7.0
13.9
0.0
7.0
14.0
7.0
14.0
0.0
6.6
13.1
6.6
13.1
0.0
7.0
14.0
7.0
14.0
WEV
0.31
0.30
0.56
0.55
0.35
0.34
0.54
0.55
0.32
0.32
0.48
0.50
0.34
0.34
0.49
0.48
0.50
0.49
0.28
0.31

Chapter 5: Simulation – Results
Overview of all Powertrain Technologies in the
Middle-Sized Class, NEDC
App. 5-55
Fuel Consumption
Powertrain
Technology
ICEV-G
ICEV-D
HV-G
HV-D
Fuel Cell
Vehicle Weight
Weight Engine / Motor
absolute Reduction Reduction absolute Reduction Reduction
Power
Saving
[l/100km] [l/100km]
[%]
[kg]
[kg]
[%]
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
9.66
9.54
9.43
9.15
8.67
7.50
7.37
7.26
7.14
6.80
6.23
6.05
5.78
5.96
5.66
4.80
4.70
4.60
4.60
4.43
3.06
2.97
2.88
2.95
2.83
0.12
0.23
0.52
1.00
0.13
0.24
0.36
0.71
0.18
0.45
0.27
0.57
0.09
0.19
0.19
0.37
0.09
0.18
0.11
0.23
0.0
1.3
2.4
5.3
10.3
0.0
1.8
3.2
4.8
9.4
0.0
2.9
7.2
4.4
9.2
0.0
1.9
4.0
4.0
7.6
0.0
3.0
5.8
3.7
7.6
1640
1536
1432
1536
1432
1740
1636
1532
1636
1532
1752
1648
1544
1648
1544
1852
1748
1644
1748
1644
1752
1648
1544
1648
1544
104
208
104
208
104
208
104
208
104
208
104
208
104
208
104
208
104
208
104
208
0.0
6.3
12.7
6.3
12.7
0.0
6.0
12.0
6.0
12.0
0.0
5.9
11.9
5.9
11.9
0.0
5.6
11.2
5.6
11.2
0.0
5.9
11.9
5.9
11.9
WEV
0.20
0.19
0.84
0.81
0.29
0.27
0.81
0.79
0.48
0.61
0.74
0.78
0.35
0.36
0.72
0.68
0.50
0.49
0.62
0.64

Chapter 5: Simulation – Results
Overview of all Powertrain Technologies in the
Middle-Sized Class, HYZEM
App. 5-56
Fuel Consumption
Powertrain
Technology
ICEV-G
ICEV-D
HV-G
HV-D
Fuel Cell
Vehicle Weight
Weight Engine / Motor
Power
absolute Reduction Reduction absolute Reduction Reduction
Saving
[l/100km] [l/100km]
[%]
[kg]
[kg]
[%]
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
8.07
7.90
7.74
7.71
7.37
6.15
6.03
5.90
5.90
5.67
7.33
7.15
6.96
7.12
6.84
5.62
5.49
5.38
5.43
5.26
3.54
3.43
3.33
3.44
3.33
0.17
0.33
0.35
0.70
0.12
0.25
0.24
0.48
0.18
0.37
0.21
0.49
0.12
0.24
0.19
0.36
0.11
0.21
0.10
0.21
0.0
2.1
4.1
4.4
8.6
0.0
2.0
4.0
4.0
7.8
0.0
2.4
5.1
2.8
6.6
0.0
2.2
4.2
3.4
6.5
0.0
3.0
6.0
2.8
6.0
1640
1536
1432
1536
1432
1740
1636
1532
1636
1532
1752
1648
1544
1648
1544
1852
1748
1644
1748
1644
1752
1648
1544
1648
1544
104
208
104
208
104
208
104
208
104
208
104
208
104
208
104
208
104
208
104
208
0.0
6.3
12.7
6.3
12.7
0.0
6.0
12.0
6.0
12.0
0.0
5.9
11.9
5.9
11.9
0.0
5.6
11.2
5.6
11.2
0.0
5.9
11.9
5.9
11.9
WEV
0.33
0.32
0.69
0.68
0.33
0.34
0.66
0.66
0.40
0.43
0.48
0.56
0.39
0.38
0.60
0.58
0.51
0.51
0.48
0.50

App. 5-57
Chapter 5: Simulation – Results
Overview of all Powertrain Technologies in
SUV, NEDC
Vehicle Weight
Fuel Consumption
Powertrain
Technology
ICEV-G
ICEV-D
HV-G
HV-D
Fuel Cell
Weight Engine / Motor
absolute Reduction Reduction absolute Reduction Reduction
Power
Saving
[kg]
[%]
[kg]
[l/100km] [l/100km]
[%]
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
13.69
13.48
13.29
13.07
12.38
9.72
9.56
9.41
9.31
8.89
8.90
8.75
8.58
8.65
8.34
7.01
6.84
6.65
6.77
6.53
4.15
4.04
3.92
4.00
3.86
0.21
0.41
0.63
1.32
0.16
0.31
0.40
0.83
0.15
0.31
0.25
0.56
0.17
0.36
0.24
0.48
0.12
0.24
0.15
0.29
0.0
1.6
3.0
4.6
9.6
0.0
1.6
3.2
4.2
8.5
0.0
1.6
3.5
2.8
6.2
0.0
2.5
5.1
3.5
6.9
0.0
2.9
5.7
3.7
7.1
2195
2055
1914
2055
1914
2320
2180
2039
2180
2039
2345
2205
2064
2205
2064
2470
2330
2189
2330
2189
2345
2205
2064
2205
2064
140
281
140
281
140
281
140
281
140
281
140
281
140
281
140
281
140
281
140
281
0.0
6.4
12.8
6.4
12.8
0.0
6.1
12.1
6.1
12.1
0.0
6.0
12.0
6.0
12.0
0.0
5.7
11.4
5.7
11.4
0.0
6.0
12.0
6.0
12.0
WEV
0.25
0.23
0.72
0.75
0.27
0.26
0.69
0.71
0.28
0.29
0.47
0.52
0.44
0.45
0.61
0.60
0.48
0.47
0.62
0.59

App. 5-58
Chapter 5: Simulation – Results
Overview of All Powertrain Technologies in
SUV, HYZEM
Vehicle Weight
Fuel Consumption
Powertrain
Technology
ICEV-G
ICEV-D
HV-G
HV-D
Fuel Cell
Weight Engine / Motor
absolute Reduction Reduction absolute Reduction Reduction
Saving
Power
[kg]
[l/100km] [l/100km]
[%]
[kg]
[%]
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
Min WS
Max WS
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
base
same as base
same as base
downsized 1
downsized 2
11.59
11.36
11.14
11.17
10.74
9.13
8.95
8.77
8.83
8.51
10.92
10.70
10.49
10.57
10.21
8.57
8.42
8.24
8.33
8.05
5.09
4.95
4.81
4.94
4.81
0.23
0.45
0.41
0.85
0.18
0.36
0.30
0.62
0.22
0.44
0.35
0.72
0.15
0.33
0.24
0.52
0.14
0.28
0.15
0.28
0.0
2.0
3.8
3.6
7.3
0.0
2.0
3.9
3.3
6.8
0.0
2.0
4.0
3.2
6.6
0.0
1.8
3.8
2.8
6.0
0.0
2.8
5.5
2.9
5.4
2195
2055
1914
2055
1914
2320
2180
2039
2180
2039
2345
2205
2064
2205
2064
2470
2330
2189
2330
2189
2345
2205
2064
2205
2064
140
281
140
281
140
281
140
281
140
281
140
281
140
281
140
281
140
281
140
281
0.0
6.4
12.8
6.4
12.8
0.0
6.1
12.1
6.1
12.1
0.0
6.0
12.0
6.0
12.0
0.0
5.7
11.4
5.7
11.4
0.0
6.0
12.0
6.0
12.0
WEV
0.31
0.30
0.56
0.57
0.33
0.32
0.55
0.56
0.34
0.33
0.54
0.55
0.31
0.34
0.50
0.53
0.46
0.46
0.48
0.45

App. 5-59
Chapter 5: Simulation – Results
Summary
At 10 % weight saving and without powertrain re-sizing the percentage
fuel consumption reductions are as follows:
NEDC
ICEV-G
NEDC
ICEV-D
NEDC
HV-G
NEDC
HV-D
NEDC
FCV
HYZEM
ICEV-G
HYZEM
ICEV-D
HYZEM
HV-G
HYZEM
HV-D
HYZEM
FCV
Compact
Class
-2.6 %
-3.5 %
-3.9 %
-3.1 %
-5.3 %
-3.1 %
-3.4 %
-3.2 %
-3.4 %
-4.9 %
Mid-Size
Class
-1.9 %
-2.7 %
-5.8 %
-3.6 %
-4.9 %
-3.2 %
-3.4 %
-4.2 %
-3.8 %
-5.1 %
SUV
-2.4 %
-2.6 %
-2.9 %
-4.5 %
-4.7 %
-3.0 %
-3.2 %
-3.4 %
-3.3 %
-4.6 %
At 10 % weight saving and with powertrain re-sizing the percentage fuel
consumption reductions are as follows:
NEDC
ICEV-G
NEDC
ICEV-D
NEDC
HV-G
NEDC
HV-D
NEDC
FCV
HYZEM
ICEV-G
HYZEM
ICEV-D
HYZEM
HV-G
HYZEM
HV-D
HYZEM
FCV
Compact
Class
-6.8 %
-7.1 %
-5.7 %
-4.9 %
-4.9 %
-5.5 %
-5.5 %
-4.9 %
-4.8 %
-3.0 %
Mid-Size
Class
-8.2 %
-7.9 %
-7.7 %
-7.0 %
-6.3 %
-6.8 %
-6.6 %
-5.4 %
-5.9 %
-5.0 %
SUV
-7.4 %
-7.1 %
-5.1 %
-6.0 %
-5.9 %
-5.7 %
-5.6 %
-5.5 %
-5.2 %
-4.6 %
